find each missing length. if necessary, round to the ......find each missing length. if necessary,...

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Find each missing length. If necessary, round to the nearest hundredth. 1. SOLUTION: Use the Pythagorean Theorem, substituting 3 for a and 4 for b. 2. SOLUTION: Use the Pythagorean Theorem, substituting 4 for a and 21 for c. eSolutions Manual - Powered by Cognero Page 1 10 - 5 The Pythagorean Theorem

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Page 1: Find each missing length. If necessary, round to the ......Find each missing length. If necessary, round to the nearest hundredth. 62/87,21 Use the Pythagorean Theorem, substituting

Find each missing length. If necessary, round to the nearest hundredth.

1. 

SOLUTION:  Use the Pythagorean Theorem, substituting 3 for a and 4 for b.

2. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 21 for c.

3. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for b and 19 for c.

4. 

SOLUTION:  Use the Pythagorean Theorem, substituting 8 for a and 12 for b.

5. BASEBALL  A baseball diamond is a square. The distance between consecutive bases is 90 feet.

a.  How far does a catcher have to throw the ball from home plate to second base? b.  How far does a third baseman throw the ball to the first baseman from a point in the baseline 15 feet from third to second base? c.  A base runner going from first to second base is 100 feet from home plate. How far is the runner from second base?

SOLUTION:  a. Use the Pythagorean Theorem, substituting 90 for a and 90 for b.

The catcher has to throw the ball about 127 ft from home plate to second base.   b. The diagram below illustrates the throw made by the third baseman.

The length of a is 90 – 15 or 75 feet. Find the length of the throw c by using the Pythagorean Theorem, substituting 75 for a and 90 for b.

The third baseman has to throw the ball about 117 feet to the first baseman.   c. The diagram below illustrates the position of the base runner.

Use the Pythagorean Theorem to find the length of side a by substituting 90 for b and 100 for c.

So, the base runner is about 44 feet from first base to second base. Therefore, the distance the base runner is from second is about 90 – 44 or 46 feet.  

Determine whether each set of measures can be the lengths of the sides of a right triangle.6. 8, 12, 16

SOLUTION:  

Since the measure of the longest side is 16, let c = 16, a = 8, and b = 12. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 8, 12, and 16 is not a right triangle.

7. 28, 45, 53

SOLUTION:  

Since the measure of the longest side is 53, let c = 53, a = 28, and b = 45. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 28, 45, and 53 is a right triangle.

8. 7, 24, 25

SOLUTION:  

Since the measure of the longest side is 25, let c = 25, a = 7, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 7, 24, and 25 is a right triangle.

9. 15, 25, 45

SOLUTION:  

Since the measure of the longest side is 45, let c = 45, a = 15, and b = 25. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 15, 25, and 45 is not a right triangle.

Find each missing length. If necessary, round to the nearest hundredth.

10. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for a and 14 for b.

11. 

SOLUTION:  Use the Pythagorean Theorem, substituting 2 for a and 12 for c.

12. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and 20 for b.

13. 

SOLUTION:  Use the Pythagorean Theorem, substituting 9 for b and 31 for c.

14. 

SOLUTION:  Use the Pythagorean Theorem, substituting 16 for a and 26 for c.

15. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and  for b.

16. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for b and 25 for c.

17. 

SOLUTION:  

Use the Pythagorean Theorem, substituting 5 for a and  for c.

18. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for b and  for c.

19. TELEVISION  Larry is buying an entertainment stand for his television. The diagonal of his television is 42 inches. The space for the television measures 30 inches by 36 inches. Will Larry’s television fit? Explain.

SOLUTION:  Use the Pythagorean Theorem, substituting 30 for a and 36 for b.

Yes; sample answer: The diagonal of the space in the TV stand is about 46.9 inches, which is greater than the diagonal of the television, so Larry’s TV will fit.

Determine whether each set of measures can be the lengths of the sides of a right triangle. Then determine whether they form a Pythagorean triple.

20. 9, 40, 41

SOLUTION:  

Since the measure of the longest side is 41, let c = 41, a = 9, and b = 40. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 9, 40, and 41 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

21. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = 3, and b = . Then determine whether c2 = a

2 +

b2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 3, , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

22. 

SOLUTION:  

Since the measure of the longest side is 12, let c = 12, a = 4, and b = . Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 4, , and 12 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

23. 

SOLUTION:  

Since the measure of the longest side is 14, let c = 14, a = , and b = 7. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths , 7, and 14 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

24. 8, 31.5, 32.5

SOLUTION:  

Since the measure of the longest side is 32.5, let c = 32.5, a = 8, and b = 31.5. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 8, 31.5, and 32.5 is a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number, but b and c are not whole numbers.

25. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = , and b = . Then determine whether c2 =

a2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths , , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

26. 18, 24, 30

SOLUTION:  

Since the measure of the longest side is 30, let c = 30, a = 18, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 18, 24, and 30 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

27. 36, 77, 85

SOLUTION:  

Since the measure of the longest side is 85, let c = 85, a = 36, and b = 77. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 36, 77, and 85 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

28. 17, 33, 98

SOLUTION:  Since the measure of the longest side is 98, let c = 98, a = 17, and b = 33. The length of c is greater than the sum of a and b, so this is not a triangle. 

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 17, 33, and 98 is not a triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

29. GEOMETRY  Refer to the triangle shown.

a.  What is a? b.  Find the area of the triangle.

SOLUTION:  a. Use the Pythagorean Theorem, substituting 11 for b and 23 for c.

b.

The area of the triangle is about 111.1 units2.

30. GARDENING  Khaliah wants to plant flowers in a triangular plot. She has three lengths of plastic garden edging that measure 8 feet, 15 feet, and 17 feet. Determine whether these pieces form a right triangle. Explain.

SOLUTION:  Yes; sample answer: The longest side is 17 feet so this has to be the hypotenuse.

82 + 15

2 = 17

2 so the pieces form a right triangle by the converse of the Pythagorean Theorem.

31. LADDER  Mr. Takeo is locked out of his house. The only open window is on the second floor. There is a bush along the edge of the house, so he places the neighbor’s ladder 10 feet from the house. To the nearest foot, what length of ladder does he need to reach the window?

SOLUTION:  Use the Pythagorean Theorem, substituting 10 for a and 28 for b.

He will need a 30-ft ladder to reach the window.

CCSS TOOLS  Find the length of the hypotenuse. Round to the nearest hundredth.

32. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for a and 10 for b.

33. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 7 for b.

34. DOLLHOUSE  Alonso is building a dollhouse for his sister’s birthday. The roof is 24 inches across and the slanted side is 16 inches long as shown. Find the height of the roof to the nearest tenth of an inch.

SOLUTION:  Use the Pythagorean Theorem, substituting 12 for b and 16 for c.

The height of the roof is 10.6 in.

35. GEOMETRY  Each side of a cube is 5 inches long. Find the length of a diagonal of the cube.

SOLUTION:  

Use the Pythagorean Theorem to find the diagonal of a side of the cube, substituting 5 for a and 5 for b.

Then, use the Pythagorean Theorem to find a diagonal of the cube, substituting 5 for a and  for b.

The length of a diagonal of the cube is about 8.66 in.

36. TOWN SQUARES  The largest town square in the world is Tiananmen Square in Beijing, China, covering 98 acres. a.  One square mile is 640 acres. Assuming that Tiananmen Square is a square, how many feet long is a side to the nearest foot? b.  To the nearest foot, what is the diagonal distance across Tiananmen Square?

SOLUTION:  a. First, use the conversion factor 1 square mile = 640 acres to convert the area of the square from acres to square miles.

So, 98 acres is 0.153125 square miles. Use dimensional analysis to convert this measure to square feet.  

  Next, use the formula for the area of a square to find the length of a side.

Therefore, a side of Tiananmen Square is about 2066 feet long.   b. Use the Pythagorean Theorem to find the length of the diagonal of the square, substituting 2066 for both a and b.

The diagonal distance across Tiananmen Square is about 2922 feet.

37. TRUCKS  Violeta needs to construct a ramp to roll a cart of moving boxes from her garage into the back of her truck. The truck is 6 feet from the garage. The back of the truck is 36 inches above the ground. How long does the ramp have to be?

SOLUTION:  First, rewrite 36 inches as 3 ft. Use the Pythagorean thereom, substituting 6 for a and 3 for b.

The ramp must be about 6.7 ft.

If c is the measure of the hypotenuse of a right triangle, find each missing measure. If necessary, round to the nearest hundredth.

38. a = x, b = x + 41, c = 85

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 36; b = 77

39. a = 8, b = x, c = x + 2

SOLUTION:  

b = 15; c = 17

40. a = 12, b = x − 2, c = x

SOLUTION:  

b = 35; c = 37

41. a = x, b = x + 7, c = 97

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 65; b = 72

42. a = x − 47, b = x, c = x + 2

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 16; b = 63; c = 65

43. a = x − 32, b = x − 1, c = x

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 9; b = 40; c = 41

44. GEOMETRY  A right triangle has one leg that is 8 inches shorter than the other leg. The hypotenuse is 30 inches long. Find the length of each leg.

SOLUTION:  

The length of each leg of the triangle is about 24.83 in. and about 16.83 in.

45. MULTIPLE REPRESENTATIONS In this problem, you will derive a method for finding the midpoint and length of a segment on the coordinate plane. a. Graphical Use a graph to find the lengths of the segments between (3, 2) and (8, 2) and between (4, 1) and (4, 9).Then find the midpoint of each segment. b. Logical Use what you learned in part a to write expressions for the lengths of the segments between (x1 , y) and

(x2 , y) and between (x, y1 ) and (x,  y2). What would be the midpoint of each segment?

c. Analytical Based on your results from part b, find the midpoint of the segment with endpoints at (x1, y1), and (x2,

y2).

d. Analytical Use the Pythagorean Theorem to write an expression for the distance between (x1, y1), and (x2, y2).

SOLUTION:  a.  From the graph, the length of the vertical segment is 9 – 1 or 8 units and the length of the horizontal line is 8 – 3 or 5 units.

The midpoints will be located in the middle of each segment, or the average of the coordinates. For the vertical segment, the value between 1 and 9 is 5, so the midpoint should be at (4, 5). For the horizontal segment, the value between 3 and 8 is 5.5, so the midpoint should be at (5.5, 2). b.  Distance: The length of the segment between (x1, y) and (x2, y) will be the absolute value of x1 – x2. The length

of the segment between (x, y1) and (x, y2) will be the absolute value of y1 – y2.

Midpoint: When the x-coordinates are identical, then the x-coordinate of the midpoint will also be the same value.

This is true for the y-coordinates as well. The midpoint of (x1, y) and (x2, y) is at the average of the x-coordinates

and y or at , and the midpoint of (x, y1) and (x, y2) is at .

c. When the x- and y-coordinates are both different, the midpoint should be at the average values of the coordinates,

or at .   d. Form a right triangle with the segment formed by the two points as the hypotenuse. Note that the other coordinateis (x2, y1) in the drawing. 

 

We know the Pythagorean Theorem is a2 + b

2 = c

2. We can solve this formula for c by taking the square root of

each side. So, . Now we can replace the variables with the lengths of each side. The length of

side a is x2 – x1. The length of side b is y2 – y1. The length of side c is now .

 

46. ERROR ANALYSIS  Wyatt and Dario are determining whether 36, 77, and 85 form a Pythagorean triple. Is eitherof them correct? Explain your reasoning.

SOLUTION:  Wyatt is correct. The square of the greatest value should be equal to the sum of the squares of the two smaller values.  Since this is the case, the numbers form a Pythagorean triple.

47. CCSS PERSEVERANCE  Find the value of x in the figure shown.

SOLUTION:  The figure can be separated into two right triangles. Let m represent the missing side length common to both right

triangles. From the Pythagorean Theorem, m2 = 2

2 + x

2 and 14

2 = 8

2 + m

2. Using substitution, you can find that 2

2 +

x2 = 14

2 – 8

2.

Solve for x.

48. REASONING  Provide a counterexample to the statement. Any two right triangles with the same hypotenuse have the same area.

SOLUTION:  Different lengths of a and b can produce the same value of c in the Pythagorean theorem.  

 

Sample answer: A right triangle with legs measuring 3 cm and 4 cm has a hypotenuse of 5 cm and an area of 6 cm2.

A right triangle with legs measuring 2 cm and  cm also has a hypotenuse of 5 cm, but its area is   cm2,

which is not equivalent to 6 cm2.

49. OPEN ENDED  Draw a right triangle that has a hypotenuse of  units.

SOLUTION:  Use the Pythagorean Theorem to select two side lengths for a and b with the given value of c.

 

50. WRITING IN MATH  Explain how to determine whether segments in three lengths could form a right triangle.

SOLUTION:  

From the converse of the Pythagorean Theorem, if a2 + b

2 = c

2 then a, b, and c are the lengths of the side of a right

triangle. So, check to see whether the square of the greatest number is equal to the sum of the squares of the other two numbers. Consider triangle with sides of 9, 12 and 15 and a triangle with sides of 7, 13 and 19. 

   

51. GEOMETRY  Find the missing length.

A  −17

B  −

C  

D  17

SOLUTION:  

The correct choice is C.

52. What is a solution of this equation?

F  0, 3 G  3 H  0 J  no solutions

SOLUTION:  

The correct choice is H.

53. SHORT RESPONSE  A plumber charges $40 for the first hour of each house call plus $8 for each additional half hour. If the plumber works for 4 hours, how much does he charge?

SOLUTION:  Let x = the total number of hours worked.

The plumber charges $88 for 4 hours of work.

54. Find the next term in the geometric sequence .

A  

B  

C   

D  

SOLUTION:  

The correct choice is B.

Solve each equation. Check your solution.

55. 

SOLUTION:  

Check.

56. 

SOLUTION:  

Check.

57. 

SOLUTION:  

Check.

58. 

SOLUTION:  

Check.

59. 

SOLUTION:  

Check.

60. 

SOLUTION:  

Check.

There is no real solution.

Simplify each expression.

61. 

SOLUTION:  

62. 

SOLUTION:  

63. 

SOLUTION:  

64. 

SOLUTION:  

65. 

SOLUTION:  

66. 

SOLUTION:  

Describe how the graph of each function is related to the graph of f (x) = x2.

67. g(x) = x2 − 8

SOLUTION:  

The graph of f (x) = x2 + c represents a vertical translation of the parent graph. The value of c is –8, and –8 < 0. If c

< 0, the graph of f (x) = x2 is translated  units down. Therefore, the graph of g(x) = x

2 – 8 is a translation of the

parent graph shifted down 8 units.

68. h(x) = x2

SOLUTION:  

The graph of f (x) = ax2 stretches or compresses the graph of f (x) = x

2 vertically. The value of a is , and 0 <  <

1. If 0 <  < 1, the graph of f (x) = x2 is compressed vertically. Therefore, the graph of h(x) = x

2 is the parent

graph compressed vertically.

69. h(x) = −x2 + 5

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is 5, and 5 > 0. If c > 0, the graph of f (x) = x2 is translated

 units up. Therefore, the graph of h(x) = −x2 + 5 is a translation of the parent graph shifted up 8 units and

reflected across the x-axis.

70. g(x) = (x + 10)2

SOLUTION:  

The graph of f (x) = (x – c)2 represents a horizontal translation of the parent graph. The value of c is –10, and –10 <

0. If c < 0, the graph of f (x) = (x – c)2

is translated  units left. Therefore, the graph of g(x) = (x + 10)2 is a

translation of the parent graph shifted left 10 units.

71. g(x) = −2x2

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = ax

2 stretches or

compresses the graph of f (x) = x2 vertically. The value of a is –2, and |–2| > 1. If  > 1, the graph of f (x) = x

2 is

stretched vertically. Therefore, the graph of g(x) = –2x2 is the parent graph reflected across the x-axis and stretched

vertically.

72. h(x) = −x2 −

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is , and < 0. If c < 0, the graph of f (x) = x2 is

translated  units down. Therefore, the graph of h(x) = −x2 is a translation of the parent graph shifted down

 units and reflected across the x-axis.

73. ROCK CLIMBING  While rock climbing, Damaris launches a grappling hook from a height of 6 feet with an initialupward velocity of 56 feet per second. The hook just misses the stone ledge that she wants to scale. As it falls, the hook anchors on a ledge 30 feet above the ground. How long was the hook in the air?

SOLUTION:  

A half second after she throws the hook, it is 30 feet in the air. The hook continues up, then drops back down to the height of 30 feet 3 seconds after the throw. The hook was in the air for 3 seconds.

Find each product.74. (b + 8)(b + 2)

SOLUTION:  

75. (x − 4)(x − 9)

SOLUTION:  

76. (y + 4)(y − 8)

SOLUTION:  

77. (p + 2)(p − 10)

SOLUTION:  

78. (2w − 5)(w + 7)

SOLUTION:  

79. (8d + 3)(5d + 2)

SOLUTION:  

80. BUSINESS  The amount of money spent at West Outlet Mall continues to increase. The total T(x) in millions of

dollars can be estimated by the function T(x) = 12(1.12)x, where x is the number of years after it opened in 2005.

Find the amount of sales in 2015, 2016, and 2017.

SOLUTION:  

The sales for the mall in 2015 will be about $37.27 million; in 2016 will be about $41.74 million; and in 2017 will be about $46.75 million.

Solve each proportion.

81. 

SOLUTION:  

82. 

SOLUTION:  

83. 

SOLUTION:  

84. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 1

10-5 The Pythagorean Theorem

Page 2: Find each missing length. If necessary, round to the ......Find each missing length. If necessary, round to the nearest hundredth. 62/87,21 Use the Pythagorean Theorem, substituting

Find each missing length. If necessary, round to the nearest hundredth.

1. 

SOLUTION:  Use the Pythagorean Theorem, substituting 3 for a and 4 for b.

2. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 21 for c.

3. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for b and 19 for c.

4. 

SOLUTION:  Use the Pythagorean Theorem, substituting 8 for a and 12 for b.

5. BASEBALL  A baseball diamond is a square. The distance between consecutive bases is 90 feet.

a.  How far does a catcher have to throw the ball from home plate to second base? b.  How far does a third baseman throw the ball to the first baseman from a point in the baseline 15 feet from third to second base? c.  A base runner going from first to second base is 100 feet from home plate. How far is the runner from second base?

SOLUTION:  a. Use the Pythagorean Theorem, substituting 90 for a and 90 for b.

The catcher has to throw the ball about 127 ft from home plate to second base.   b. The diagram below illustrates the throw made by the third baseman.

The length of a is 90 – 15 or 75 feet. Find the length of the throw c by using the Pythagorean Theorem, substituting 75 for a and 90 for b.

The third baseman has to throw the ball about 117 feet to the first baseman.   c. The diagram below illustrates the position of the base runner.

Use the Pythagorean Theorem to find the length of side a by substituting 90 for b and 100 for c.

So, the base runner is about 44 feet from first base to second base. Therefore, the distance the base runner is from second is about 90 – 44 or 46 feet.  

Determine whether each set of measures can be the lengths of the sides of a right triangle.6. 8, 12, 16

SOLUTION:  

Since the measure of the longest side is 16, let c = 16, a = 8, and b = 12. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 8, 12, and 16 is not a right triangle.

7. 28, 45, 53

SOLUTION:  

Since the measure of the longest side is 53, let c = 53, a = 28, and b = 45. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 28, 45, and 53 is a right triangle.

8. 7, 24, 25

SOLUTION:  

Since the measure of the longest side is 25, let c = 25, a = 7, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 7, 24, and 25 is a right triangle.

9. 15, 25, 45

SOLUTION:  

Since the measure of the longest side is 45, let c = 45, a = 15, and b = 25. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 15, 25, and 45 is not a right triangle.

Find each missing length. If necessary, round to the nearest hundredth.

10. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for a and 14 for b.

11. 

SOLUTION:  Use the Pythagorean Theorem, substituting 2 for a and 12 for c.

12. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and 20 for b.

13. 

SOLUTION:  Use the Pythagorean Theorem, substituting 9 for b and 31 for c.

14. 

SOLUTION:  Use the Pythagorean Theorem, substituting 16 for a and 26 for c.

15. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and  for b.

16. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for b and 25 for c.

17. 

SOLUTION:  

Use the Pythagorean Theorem, substituting 5 for a and  for c.

18. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for b and  for c.

19. TELEVISION  Larry is buying an entertainment stand for his television. The diagonal of his television is 42 inches. The space for the television measures 30 inches by 36 inches. Will Larry’s television fit? Explain.

SOLUTION:  Use the Pythagorean Theorem, substituting 30 for a and 36 for b.

Yes; sample answer: The diagonal of the space in the TV stand is about 46.9 inches, which is greater than the diagonal of the television, so Larry’s TV will fit.

Determine whether each set of measures can be the lengths of the sides of a right triangle. Then determine whether they form a Pythagorean triple.

20. 9, 40, 41

SOLUTION:  

Since the measure of the longest side is 41, let c = 41, a = 9, and b = 40. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 9, 40, and 41 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

21. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = 3, and b = . Then determine whether c2 = a

2 +

b2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 3, , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

22. 

SOLUTION:  

Since the measure of the longest side is 12, let c = 12, a = 4, and b = . Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 4, , and 12 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

23. 

SOLUTION:  

Since the measure of the longest side is 14, let c = 14, a = , and b = 7. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths , 7, and 14 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

24. 8, 31.5, 32.5

SOLUTION:  

Since the measure of the longest side is 32.5, let c = 32.5, a = 8, and b = 31.5. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 8, 31.5, and 32.5 is a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number, but b and c are not whole numbers.

25. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = , and b = . Then determine whether c2 =

a2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths , , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

26. 18, 24, 30

SOLUTION:  

Since the measure of the longest side is 30, let c = 30, a = 18, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 18, 24, and 30 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

27. 36, 77, 85

SOLUTION:  

Since the measure of the longest side is 85, let c = 85, a = 36, and b = 77. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 36, 77, and 85 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

28. 17, 33, 98

SOLUTION:  Since the measure of the longest side is 98, let c = 98, a = 17, and b = 33. The length of c is greater than the sum of a and b, so this is not a triangle. 

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 17, 33, and 98 is not a triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

29. GEOMETRY  Refer to the triangle shown.

a.  What is a? b.  Find the area of the triangle.

SOLUTION:  a. Use the Pythagorean Theorem, substituting 11 for b and 23 for c.

b.

The area of the triangle is about 111.1 units2.

30. GARDENING  Khaliah wants to plant flowers in a triangular plot. She has three lengths of plastic garden edging that measure 8 feet, 15 feet, and 17 feet. Determine whether these pieces form a right triangle. Explain.

SOLUTION:  Yes; sample answer: The longest side is 17 feet so this has to be the hypotenuse.

82 + 15

2 = 17

2 so the pieces form a right triangle by the converse of the Pythagorean Theorem.

31. LADDER  Mr. Takeo is locked out of his house. The only open window is on the second floor. There is a bush along the edge of the house, so he places the neighbor’s ladder 10 feet from the house. To the nearest foot, what length of ladder does he need to reach the window?

SOLUTION:  Use the Pythagorean Theorem, substituting 10 for a and 28 for b.

He will need a 30-ft ladder to reach the window.

CCSS TOOLS  Find the length of the hypotenuse. Round to the nearest hundredth.

32. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for a and 10 for b.

33. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 7 for b.

34. DOLLHOUSE  Alonso is building a dollhouse for his sister’s birthday. The roof is 24 inches across and the slanted side is 16 inches long as shown. Find the height of the roof to the nearest tenth of an inch.

SOLUTION:  Use the Pythagorean Theorem, substituting 12 for b and 16 for c.

The height of the roof is 10.6 in.

35. GEOMETRY  Each side of a cube is 5 inches long. Find the length of a diagonal of the cube.

SOLUTION:  

Use the Pythagorean Theorem to find the diagonal of a side of the cube, substituting 5 for a and 5 for b.

Then, use the Pythagorean Theorem to find a diagonal of the cube, substituting 5 for a and  for b.

The length of a diagonal of the cube is about 8.66 in.

36. TOWN SQUARES  The largest town square in the world is Tiananmen Square in Beijing, China, covering 98 acres. a.  One square mile is 640 acres. Assuming that Tiananmen Square is a square, how many feet long is a side to the nearest foot? b.  To the nearest foot, what is the diagonal distance across Tiananmen Square?

SOLUTION:  a. First, use the conversion factor 1 square mile = 640 acres to convert the area of the square from acres to square miles.

So, 98 acres is 0.153125 square miles. Use dimensional analysis to convert this measure to square feet.  

  Next, use the formula for the area of a square to find the length of a side.

Therefore, a side of Tiananmen Square is about 2066 feet long.   b. Use the Pythagorean Theorem to find the length of the diagonal of the square, substituting 2066 for both a and b.

The diagonal distance across Tiananmen Square is about 2922 feet.

37. TRUCKS  Violeta needs to construct a ramp to roll a cart of moving boxes from her garage into the back of her truck. The truck is 6 feet from the garage. The back of the truck is 36 inches above the ground. How long does the ramp have to be?

SOLUTION:  First, rewrite 36 inches as 3 ft. Use the Pythagorean thereom, substituting 6 for a and 3 for b.

The ramp must be about 6.7 ft.

If c is the measure of the hypotenuse of a right triangle, find each missing measure. If necessary, round to the nearest hundredth.

38. a = x, b = x + 41, c = 85

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 36; b = 77

39. a = 8, b = x, c = x + 2

SOLUTION:  

b = 15; c = 17

40. a = 12, b = x − 2, c = x

SOLUTION:  

b = 35; c = 37

41. a = x, b = x + 7, c = 97

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 65; b = 72

42. a = x − 47, b = x, c = x + 2

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 16; b = 63; c = 65

43. a = x − 32, b = x − 1, c = x

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 9; b = 40; c = 41

44. GEOMETRY  A right triangle has one leg that is 8 inches shorter than the other leg. The hypotenuse is 30 inches long. Find the length of each leg.

SOLUTION:  

The length of each leg of the triangle is about 24.83 in. and about 16.83 in.

45. MULTIPLE REPRESENTATIONS In this problem, you will derive a method for finding the midpoint and length of a segment on the coordinate plane. a. Graphical Use a graph to find the lengths of the segments between (3, 2) and (8, 2) and between (4, 1) and (4, 9).Then find the midpoint of each segment. b. Logical Use what you learned in part a to write expressions for the lengths of the segments between (x1 , y) and

(x2 , y) and between (x, y1 ) and (x,  y2). What would be the midpoint of each segment?

c. Analytical Based on your results from part b, find the midpoint of the segment with endpoints at (x1, y1), and (x2,

y2).

d. Analytical Use the Pythagorean Theorem to write an expression for the distance between (x1, y1), and (x2, y2).

SOLUTION:  a.  From the graph, the length of the vertical segment is 9 – 1 or 8 units and the length of the horizontal line is 8 – 3 or 5 units.

The midpoints will be located in the middle of each segment, or the average of the coordinates. For the vertical segment, the value between 1 and 9 is 5, so the midpoint should be at (4, 5). For the horizontal segment, the value between 3 and 8 is 5.5, so the midpoint should be at (5.5, 2). b.  Distance: The length of the segment between (x1, y) and (x2, y) will be the absolute value of x1 – x2. The length

of the segment between (x, y1) and (x, y2) will be the absolute value of y1 – y2.

Midpoint: When the x-coordinates are identical, then the x-coordinate of the midpoint will also be the same value.

This is true for the y-coordinates as well. The midpoint of (x1, y) and (x2, y) is at the average of the x-coordinates

and y or at , and the midpoint of (x, y1) and (x, y2) is at .

c. When the x- and y-coordinates are both different, the midpoint should be at the average values of the coordinates,

or at .   d. Form a right triangle with the segment formed by the two points as the hypotenuse. Note that the other coordinateis (x2, y1) in the drawing. 

 

We know the Pythagorean Theorem is a2 + b

2 = c

2. We can solve this formula for c by taking the square root of

each side. So, . Now we can replace the variables with the lengths of each side. The length of

side a is x2 – x1. The length of side b is y2 – y1. The length of side c is now .

 

46. ERROR ANALYSIS  Wyatt and Dario are determining whether 36, 77, and 85 form a Pythagorean triple. Is eitherof them correct? Explain your reasoning.

SOLUTION:  Wyatt is correct. The square of the greatest value should be equal to the sum of the squares of the two smaller values.  Since this is the case, the numbers form a Pythagorean triple.

47. CCSS PERSEVERANCE  Find the value of x in the figure shown.

SOLUTION:  The figure can be separated into two right triangles. Let m represent the missing side length common to both right

triangles. From the Pythagorean Theorem, m2 = 2

2 + x

2 and 14

2 = 8

2 + m

2. Using substitution, you can find that 2

2 +

x2 = 14

2 – 8

2.

Solve for x.

48. REASONING  Provide a counterexample to the statement. Any two right triangles with the same hypotenuse have the same area.

SOLUTION:  Different lengths of a and b can produce the same value of c in the Pythagorean theorem.  

 

Sample answer: A right triangle with legs measuring 3 cm and 4 cm has a hypotenuse of 5 cm and an area of 6 cm2.

A right triangle with legs measuring 2 cm and  cm also has a hypotenuse of 5 cm, but its area is   cm2,

which is not equivalent to 6 cm2.

49. OPEN ENDED  Draw a right triangle that has a hypotenuse of  units.

SOLUTION:  Use the Pythagorean Theorem to select two side lengths for a and b with the given value of c.

 

50. WRITING IN MATH  Explain how to determine whether segments in three lengths could form a right triangle.

SOLUTION:  

From the converse of the Pythagorean Theorem, if a2 + b

2 = c

2 then a, b, and c are the lengths of the side of a right

triangle. So, check to see whether the square of the greatest number is equal to the sum of the squares of the other two numbers. Consider triangle with sides of 9, 12 and 15 and a triangle with sides of 7, 13 and 19. 

   

51. GEOMETRY  Find the missing length.

A  −17

B  −

C  

D  17

SOLUTION:  

The correct choice is C.

52. What is a solution of this equation?

F  0, 3 G  3 H  0 J  no solutions

SOLUTION:  

The correct choice is H.

53. SHORT RESPONSE  A plumber charges $40 for the first hour of each house call plus $8 for each additional half hour. If the plumber works for 4 hours, how much does he charge?

SOLUTION:  Let x = the total number of hours worked.

The plumber charges $88 for 4 hours of work.

54. Find the next term in the geometric sequence .

A  

B  

C   

D  

SOLUTION:  

The correct choice is B.

Solve each equation. Check your solution.

55. 

SOLUTION:  

Check.

56. 

SOLUTION:  

Check.

57. 

SOLUTION:  

Check.

58. 

SOLUTION:  

Check.

59. 

SOLUTION:  

Check.

60. 

SOLUTION:  

Check.

There is no real solution.

Simplify each expression.

61. 

SOLUTION:  

62. 

SOLUTION:  

63. 

SOLUTION:  

64. 

SOLUTION:  

65. 

SOLUTION:  

66. 

SOLUTION:  

Describe how the graph of each function is related to the graph of f (x) = x2.

67. g(x) = x2 − 8

SOLUTION:  

The graph of f (x) = x2 + c represents a vertical translation of the parent graph. The value of c is –8, and –8 < 0. If c

< 0, the graph of f (x) = x2 is translated  units down. Therefore, the graph of g(x) = x

2 – 8 is a translation of the

parent graph shifted down 8 units.

68. h(x) = x2

SOLUTION:  

The graph of f (x) = ax2 stretches or compresses the graph of f (x) = x

2 vertically. The value of a is , and 0 <  <

1. If 0 <  < 1, the graph of f (x) = x2 is compressed vertically. Therefore, the graph of h(x) = x

2 is the parent

graph compressed vertically.

69. h(x) = −x2 + 5

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is 5, and 5 > 0. If c > 0, the graph of f (x) = x2 is translated

 units up. Therefore, the graph of h(x) = −x2 + 5 is a translation of the parent graph shifted up 8 units and

reflected across the x-axis.

70. g(x) = (x + 10)2

SOLUTION:  

The graph of f (x) = (x – c)2 represents a horizontal translation of the parent graph. The value of c is –10, and –10 <

0. If c < 0, the graph of f (x) = (x – c)2

is translated  units left. Therefore, the graph of g(x) = (x + 10)2 is a

translation of the parent graph shifted left 10 units.

71. g(x) = −2x2

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = ax

2 stretches or

compresses the graph of f (x) = x2 vertically. The value of a is –2, and |–2| > 1. If  > 1, the graph of f (x) = x

2 is

stretched vertically. Therefore, the graph of g(x) = –2x2 is the parent graph reflected across the x-axis and stretched

vertically.

72. h(x) = −x2 −

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is , and < 0. If c < 0, the graph of f (x) = x2 is

translated  units down. Therefore, the graph of h(x) = −x2 is a translation of the parent graph shifted down

 units and reflected across the x-axis.

73. ROCK CLIMBING  While rock climbing, Damaris launches a grappling hook from a height of 6 feet with an initialupward velocity of 56 feet per second. The hook just misses the stone ledge that she wants to scale. As it falls, the hook anchors on a ledge 30 feet above the ground. How long was the hook in the air?

SOLUTION:  

A half second after she throws the hook, it is 30 feet in the air. The hook continues up, then drops back down to the height of 30 feet 3 seconds after the throw. The hook was in the air for 3 seconds.

Find each product.74. (b + 8)(b + 2)

SOLUTION:  

75. (x − 4)(x − 9)

SOLUTION:  

76. (y + 4)(y − 8)

SOLUTION:  

77. (p + 2)(p − 10)

SOLUTION:  

78. (2w − 5)(w + 7)

SOLUTION:  

79. (8d + 3)(5d + 2)

SOLUTION:  

80. BUSINESS  The amount of money spent at West Outlet Mall continues to increase. The total T(x) in millions of

dollars can be estimated by the function T(x) = 12(1.12)x, where x is the number of years after it opened in 2005.

Find the amount of sales in 2015, 2016, and 2017.

SOLUTION:  

The sales for the mall in 2015 will be about $37.27 million; in 2016 will be about $41.74 million; and in 2017 will be about $46.75 million.

Solve each proportion.

81. 

SOLUTION:  

82. 

SOLUTION:  

83. 

SOLUTION:  

84. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 2

10-5 The Pythagorean Theorem

Page 3: Find each missing length. If necessary, round to the ......Find each missing length. If necessary, round to the nearest hundredth. 62/87,21 Use the Pythagorean Theorem, substituting

Find each missing length. If necessary, round to the nearest hundredth.

1. 

SOLUTION:  Use the Pythagorean Theorem, substituting 3 for a and 4 for b.

2. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 21 for c.

3. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for b and 19 for c.

4. 

SOLUTION:  Use the Pythagorean Theorem, substituting 8 for a and 12 for b.

5. BASEBALL  A baseball diamond is a square. The distance between consecutive bases is 90 feet.

a.  How far does a catcher have to throw the ball from home plate to second base? b.  How far does a third baseman throw the ball to the first baseman from a point in the baseline 15 feet from third to second base? c.  A base runner going from first to second base is 100 feet from home plate. How far is the runner from second base?

SOLUTION:  a. Use the Pythagorean Theorem, substituting 90 for a and 90 for b.

The catcher has to throw the ball about 127 ft from home plate to second base.   b. The diagram below illustrates the throw made by the third baseman.

The length of a is 90 – 15 or 75 feet. Find the length of the throw c by using the Pythagorean Theorem, substituting 75 for a and 90 for b.

The third baseman has to throw the ball about 117 feet to the first baseman.   c. The diagram below illustrates the position of the base runner.

Use the Pythagorean Theorem to find the length of side a by substituting 90 for b and 100 for c.

So, the base runner is about 44 feet from first base to second base. Therefore, the distance the base runner is from second is about 90 – 44 or 46 feet.  

Determine whether each set of measures can be the lengths of the sides of a right triangle.6. 8, 12, 16

SOLUTION:  

Since the measure of the longest side is 16, let c = 16, a = 8, and b = 12. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 8, 12, and 16 is not a right triangle.

7. 28, 45, 53

SOLUTION:  

Since the measure of the longest side is 53, let c = 53, a = 28, and b = 45. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 28, 45, and 53 is a right triangle.

8. 7, 24, 25

SOLUTION:  

Since the measure of the longest side is 25, let c = 25, a = 7, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 7, 24, and 25 is a right triangle.

9. 15, 25, 45

SOLUTION:  

Since the measure of the longest side is 45, let c = 45, a = 15, and b = 25. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 15, 25, and 45 is not a right triangle.

Find each missing length. If necessary, round to the nearest hundredth.

10. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for a and 14 for b.

11. 

SOLUTION:  Use the Pythagorean Theorem, substituting 2 for a and 12 for c.

12. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and 20 for b.

13. 

SOLUTION:  Use the Pythagorean Theorem, substituting 9 for b and 31 for c.

14. 

SOLUTION:  Use the Pythagorean Theorem, substituting 16 for a and 26 for c.

15. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and  for b.

16. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for b and 25 for c.

17. 

SOLUTION:  

Use the Pythagorean Theorem, substituting 5 for a and  for c.

18. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for b and  for c.

19. TELEVISION  Larry is buying an entertainment stand for his television. The diagonal of his television is 42 inches. The space for the television measures 30 inches by 36 inches. Will Larry’s television fit? Explain.

SOLUTION:  Use the Pythagorean Theorem, substituting 30 for a and 36 for b.

Yes; sample answer: The diagonal of the space in the TV stand is about 46.9 inches, which is greater than the diagonal of the television, so Larry’s TV will fit.

Determine whether each set of measures can be the lengths of the sides of a right triangle. Then determine whether they form a Pythagorean triple.

20. 9, 40, 41

SOLUTION:  

Since the measure of the longest side is 41, let c = 41, a = 9, and b = 40. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 9, 40, and 41 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

21. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = 3, and b = . Then determine whether c2 = a

2 +

b2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 3, , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

22. 

SOLUTION:  

Since the measure of the longest side is 12, let c = 12, a = 4, and b = . Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 4, , and 12 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

23. 

SOLUTION:  

Since the measure of the longest side is 14, let c = 14, a = , and b = 7. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths , 7, and 14 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

24. 8, 31.5, 32.5

SOLUTION:  

Since the measure of the longest side is 32.5, let c = 32.5, a = 8, and b = 31.5. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 8, 31.5, and 32.5 is a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number, but b and c are not whole numbers.

25. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = , and b = . Then determine whether c2 =

a2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths , , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

26. 18, 24, 30

SOLUTION:  

Since the measure of the longest side is 30, let c = 30, a = 18, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 18, 24, and 30 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

27. 36, 77, 85

SOLUTION:  

Since the measure of the longest side is 85, let c = 85, a = 36, and b = 77. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 36, 77, and 85 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

28. 17, 33, 98

SOLUTION:  Since the measure of the longest side is 98, let c = 98, a = 17, and b = 33. The length of c is greater than the sum of a and b, so this is not a triangle. 

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 17, 33, and 98 is not a triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

29. GEOMETRY  Refer to the triangle shown.

a.  What is a? b.  Find the area of the triangle.

SOLUTION:  a. Use the Pythagorean Theorem, substituting 11 for b and 23 for c.

b.

The area of the triangle is about 111.1 units2.

30. GARDENING  Khaliah wants to plant flowers in a triangular plot. She has three lengths of plastic garden edging that measure 8 feet, 15 feet, and 17 feet. Determine whether these pieces form a right triangle. Explain.

SOLUTION:  Yes; sample answer: The longest side is 17 feet so this has to be the hypotenuse.

82 + 15

2 = 17

2 so the pieces form a right triangle by the converse of the Pythagorean Theorem.

31. LADDER  Mr. Takeo is locked out of his house. The only open window is on the second floor. There is a bush along the edge of the house, so he places the neighbor’s ladder 10 feet from the house. To the nearest foot, what length of ladder does he need to reach the window?

SOLUTION:  Use the Pythagorean Theorem, substituting 10 for a and 28 for b.

He will need a 30-ft ladder to reach the window.

CCSS TOOLS  Find the length of the hypotenuse. Round to the nearest hundredth.

32. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for a and 10 for b.

33. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 7 for b.

34. DOLLHOUSE  Alonso is building a dollhouse for his sister’s birthday. The roof is 24 inches across and the slanted side is 16 inches long as shown. Find the height of the roof to the nearest tenth of an inch.

SOLUTION:  Use the Pythagorean Theorem, substituting 12 for b and 16 for c.

The height of the roof is 10.6 in.

35. GEOMETRY  Each side of a cube is 5 inches long. Find the length of a diagonal of the cube.

SOLUTION:  

Use the Pythagorean Theorem to find the diagonal of a side of the cube, substituting 5 for a and 5 for b.

Then, use the Pythagorean Theorem to find a diagonal of the cube, substituting 5 for a and  for b.

The length of a diagonal of the cube is about 8.66 in.

36. TOWN SQUARES  The largest town square in the world is Tiananmen Square in Beijing, China, covering 98 acres. a.  One square mile is 640 acres. Assuming that Tiananmen Square is a square, how many feet long is a side to the nearest foot? b.  To the nearest foot, what is the diagonal distance across Tiananmen Square?

SOLUTION:  a. First, use the conversion factor 1 square mile = 640 acres to convert the area of the square from acres to square miles.

So, 98 acres is 0.153125 square miles. Use dimensional analysis to convert this measure to square feet.  

  Next, use the formula for the area of a square to find the length of a side.

Therefore, a side of Tiananmen Square is about 2066 feet long.   b. Use the Pythagorean Theorem to find the length of the diagonal of the square, substituting 2066 for both a and b.

The diagonal distance across Tiananmen Square is about 2922 feet.

37. TRUCKS  Violeta needs to construct a ramp to roll a cart of moving boxes from her garage into the back of her truck. The truck is 6 feet from the garage. The back of the truck is 36 inches above the ground. How long does the ramp have to be?

SOLUTION:  First, rewrite 36 inches as 3 ft. Use the Pythagorean thereom, substituting 6 for a and 3 for b.

The ramp must be about 6.7 ft.

If c is the measure of the hypotenuse of a right triangle, find each missing measure. If necessary, round to the nearest hundredth.

38. a = x, b = x + 41, c = 85

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 36; b = 77

39. a = 8, b = x, c = x + 2

SOLUTION:  

b = 15; c = 17

40. a = 12, b = x − 2, c = x

SOLUTION:  

b = 35; c = 37

41. a = x, b = x + 7, c = 97

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 65; b = 72

42. a = x − 47, b = x, c = x + 2

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 16; b = 63; c = 65

43. a = x − 32, b = x − 1, c = x

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 9; b = 40; c = 41

44. GEOMETRY  A right triangle has one leg that is 8 inches shorter than the other leg. The hypotenuse is 30 inches long. Find the length of each leg.

SOLUTION:  

The length of each leg of the triangle is about 24.83 in. and about 16.83 in.

45. MULTIPLE REPRESENTATIONS In this problem, you will derive a method for finding the midpoint and length of a segment on the coordinate plane. a. Graphical Use a graph to find the lengths of the segments between (3, 2) and (8, 2) and between (4, 1) and (4, 9).Then find the midpoint of each segment. b. Logical Use what you learned in part a to write expressions for the lengths of the segments between (x1 , y) and

(x2 , y) and between (x, y1 ) and (x,  y2). What would be the midpoint of each segment?

c. Analytical Based on your results from part b, find the midpoint of the segment with endpoints at (x1, y1), and (x2,

y2).

d. Analytical Use the Pythagorean Theorem to write an expression for the distance between (x1, y1), and (x2, y2).

SOLUTION:  a.  From the graph, the length of the vertical segment is 9 – 1 or 8 units and the length of the horizontal line is 8 – 3 or 5 units.

The midpoints will be located in the middle of each segment, or the average of the coordinates. For the vertical segment, the value between 1 and 9 is 5, so the midpoint should be at (4, 5). For the horizontal segment, the value between 3 and 8 is 5.5, so the midpoint should be at (5.5, 2). b.  Distance: The length of the segment between (x1, y) and (x2, y) will be the absolute value of x1 – x2. The length

of the segment between (x, y1) and (x, y2) will be the absolute value of y1 – y2.

Midpoint: When the x-coordinates are identical, then the x-coordinate of the midpoint will also be the same value.

This is true for the y-coordinates as well. The midpoint of (x1, y) and (x2, y) is at the average of the x-coordinates

and y or at , and the midpoint of (x, y1) and (x, y2) is at .

c. When the x- and y-coordinates are both different, the midpoint should be at the average values of the coordinates,

or at .   d. Form a right triangle with the segment formed by the two points as the hypotenuse. Note that the other coordinateis (x2, y1) in the drawing. 

 

We know the Pythagorean Theorem is a2 + b

2 = c

2. We can solve this formula for c by taking the square root of

each side. So, . Now we can replace the variables with the lengths of each side. The length of

side a is x2 – x1. The length of side b is y2 – y1. The length of side c is now .

 

46. ERROR ANALYSIS  Wyatt and Dario are determining whether 36, 77, and 85 form a Pythagorean triple. Is eitherof them correct? Explain your reasoning.

SOLUTION:  Wyatt is correct. The square of the greatest value should be equal to the sum of the squares of the two smaller values.  Since this is the case, the numbers form a Pythagorean triple.

47. CCSS PERSEVERANCE  Find the value of x in the figure shown.

SOLUTION:  The figure can be separated into two right triangles. Let m represent the missing side length common to both right

triangles. From the Pythagorean Theorem, m2 = 2

2 + x

2 and 14

2 = 8

2 + m

2. Using substitution, you can find that 2

2 +

x2 = 14

2 – 8

2.

Solve for x.

48. REASONING  Provide a counterexample to the statement. Any two right triangles with the same hypotenuse have the same area.

SOLUTION:  Different lengths of a and b can produce the same value of c in the Pythagorean theorem.  

 

Sample answer: A right triangle with legs measuring 3 cm and 4 cm has a hypotenuse of 5 cm and an area of 6 cm2.

A right triangle with legs measuring 2 cm and  cm also has a hypotenuse of 5 cm, but its area is   cm2,

which is not equivalent to 6 cm2.

49. OPEN ENDED  Draw a right triangle that has a hypotenuse of  units.

SOLUTION:  Use the Pythagorean Theorem to select two side lengths for a and b with the given value of c.

 

50. WRITING IN MATH  Explain how to determine whether segments in three lengths could form a right triangle.

SOLUTION:  

From the converse of the Pythagorean Theorem, if a2 + b

2 = c

2 then a, b, and c are the lengths of the side of a right

triangle. So, check to see whether the square of the greatest number is equal to the sum of the squares of the other two numbers. Consider triangle with sides of 9, 12 and 15 and a triangle with sides of 7, 13 and 19. 

   

51. GEOMETRY  Find the missing length.

A  −17

B  −

C  

D  17

SOLUTION:  

The correct choice is C.

52. What is a solution of this equation?

F  0, 3 G  3 H  0 J  no solutions

SOLUTION:  

The correct choice is H.

53. SHORT RESPONSE  A plumber charges $40 for the first hour of each house call plus $8 for each additional half hour. If the plumber works for 4 hours, how much does he charge?

SOLUTION:  Let x = the total number of hours worked.

The plumber charges $88 for 4 hours of work.

54. Find the next term in the geometric sequence .

A  

B  

C   

D  

SOLUTION:  

The correct choice is B.

Solve each equation. Check your solution.

55. 

SOLUTION:  

Check.

56. 

SOLUTION:  

Check.

57. 

SOLUTION:  

Check.

58. 

SOLUTION:  

Check.

59. 

SOLUTION:  

Check.

60. 

SOLUTION:  

Check.

There is no real solution.

Simplify each expression.

61. 

SOLUTION:  

62. 

SOLUTION:  

63. 

SOLUTION:  

64. 

SOLUTION:  

65. 

SOLUTION:  

66. 

SOLUTION:  

Describe how the graph of each function is related to the graph of f (x) = x2.

67. g(x) = x2 − 8

SOLUTION:  

The graph of f (x) = x2 + c represents a vertical translation of the parent graph. The value of c is –8, and –8 < 0. If c

< 0, the graph of f (x) = x2 is translated  units down. Therefore, the graph of g(x) = x

2 – 8 is a translation of the

parent graph shifted down 8 units.

68. h(x) = x2

SOLUTION:  

The graph of f (x) = ax2 stretches or compresses the graph of f (x) = x

2 vertically. The value of a is , and 0 <  <

1. If 0 <  < 1, the graph of f (x) = x2 is compressed vertically. Therefore, the graph of h(x) = x

2 is the parent

graph compressed vertically.

69. h(x) = −x2 + 5

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is 5, and 5 > 0. If c > 0, the graph of f (x) = x2 is translated

 units up. Therefore, the graph of h(x) = −x2 + 5 is a translation of the parent graph shifted up 8 units and

reflected across the x-axis.

70. g(x) = (x + 10)2

SOLUTION:  

The graph of f (x) = (x – c)2 represents a horizontal translation of the parent graph. The value of c is –10, and –10 <

0. If c < 0, the graph of f (x) = (x – c)2

is translated  units left. Therefore, the graph of g(x) = (x + 10)2 is a

translation of the parent graph shifted left 10 units.

71. g(x) = −2x2

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = ax

2 stretches or

compresses the graph of f (x) = x2 vertically. The value of a is –2, and |–2| > 1. If  > 1, the graph of f (x) = x

2 is

stretched vertically. Therefore, the graph of g(x) = –2x2 is the parent graph reflected across the x-axis and stretched

vertically.

72. h(x) = −x2 −

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is , and < 0. If c < 0, the graph of f (x) = x2 is

translated  units down. Therefore, the graph of h(x) = −x2 is a translation of the parent graph shifted down

 units and reflected across the x-axis.

73. ROCK CLIMBING  While rock climbing, Damaris launches a grappling hook from a height of 6 feet with an initialupward velocity of 56 feet per second. The hook just misses the stone ledge that she wants to scale. As it falls, the hook anchors on a ledge 30 feet above the ground. How long was the hook in the air?

SOLUTION:  

A half second after she throws the hook, it is 30 feet in the air. The hook continues up, then drops back down to the height of 30 feet 3 seconds after the throw. The hook was in the air for 3 seconds.

Find each product.74. (b + 8)(b + 2)

SOLUTION:  

75. (x − 4)(x − 9)

SOLUTION:  

76. (y + 4)(y − 8)

SOLUTION:  

77. (p + 2)(p − 10)

SOLUTION:  

78. (2w − 5)(w + 7)

SOLUTION:  

79. (8d + 3)(5d + 2)

SOLUTION:  

80. BUSINESS  The amount of money spent at West Outlet Mall continues to increase. The total T(x) in millions of

dollars can be estimated by the function T(x) = 12(1.12)x, where x is the number of years after it opened in 2005.

Find the amount of sales in 2015, 2016, and 2017.

SOLUTION:  

The sales for the mall in 2015 will be about $37.27 million; in 2016 will be about $41.74 million; and in 2017 will be about $46.75 million.

Solve each proportion.

81. 

SOLUTION:  

82. 

SOLUTION:  

83. 

SOLUTION:  

84. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 3

10-5 The Pythagorean Theorem

Page 4: Find each missing length. If necessary, round to the ......Find each missing length. If necessary, round to the nearest hundredth. 62/87,21 Use the Pythagorean Theorem, substituting

Find each missing length. If necessary, round to the nearest hundredth.

1. 

SOLUTION:  Use the Pythagorean Theorem, substituting 3 for a and 4 for b.

2. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 21 for c.

3. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for b and 19 for c.

4. 

SOLUTION:  Use the Pythagorean Theorem, substituting 8 for a and 12 for b.

5. BASEBALL  A baseball diamond is a square. The distance between consecutive bases is 90 feet.

a.  How far does a catcher have to throw the ball from home plate to second base? b.  How far does a third baseman throw the ball to the first baseman from a point in the baseline 15 feet from third to second base? c.  A base runner going from first to second base is 100 feet from home plate. How far is the runner from second base?

SOLUTION:  a. Use the Pythagorean Theorem, substituting 90 for a and 90 for b.

The catcher has to throw the ball about 127 ft from home plate to second base.   b. The diagram below illustrates the throw made by the third baseman.

The length of a is 90 – 15 or 75 feet. Find the length of the throw c by using the Pythagorean Theorem, substituting 75 for a and 90 for b.

The third baseman has to throw the ball about 117 feet to the first baseman.   c. The diagram below illustrates the position of the base runner.

Use the Pythagorean Theorem to find the length of side a by substituting 90 for b and 100 for c.

So, the base runner is about 44 feet from first base to second base. Therefore, the distance the base runner is from second is about 90 – 44 or 46 feet.  

Determine whether each set of measures can be the lengths of the sides of a right triangle.6. 8, 12, 16

SOLUTION:  

Since the measure of the longest side is 16, let c = 16, a = 8, and b = 12. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 8, 12, and 16 is not a right triangle.

7. 28, 45, 53

SOLUTION:  

Since the measure of the longest side is 53, let c = 53, a = 28, and b = 45. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 28, 45, and 53 is a right triangle.

8. 7, 24, 25

SOLUTION:  

Since the measure of the longest side is 25, let c = 25, a = 7, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 7, 24, and 25 is a right triangle.

9. 15, 25, 45

SOLUTION:  

Since the measure of the longest side is 45, let c = 45, a = 15, and b = 25. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 15, 25, and 45 is not a right triangle.

Find each missing length. If necessary, round to the nearest hundredth.

10. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for a and 14 for b.

11. 

SOLUTION:  Use the Pythagorean Theorem, substituting 2 for a and 12 for c.

12. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and 20 for b.

13. 

SOLUTION:  Use the Pythagorean Theorem, substituting 9 for b and 31 for c.

14. 

SOLUTION:  Use the Pythagorean Theorem, substituting 16 for a and 26 for c.

15. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and  for b.

16. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for b and 25 for c.

17. 

SOLUTION:  

Use the Pythagorean Theorem, substituting 5 for a and  for c.

18. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for b and  for c.

19. TELEVISION  Larry is buying an entertainment stand for his television. The diagonal of his television is 42 inches. The space for the television measures 30 inches by 36 inches. Will Larry’s television fit? Explain.

SOLUTION:  Use the Pythagorean Theorem, substituting 30 for a and 36 for b.

Yes; sample answer: The diagonal of the space in the TV stand is about 46.9 inches, which is greater than the diagonal of the television, so Larry’s TV will fit.

Determine whether each set of measures can be the lengths of the sides of a right triangle. Then determine whether they form a Pythagorean triple.

20. 9, 40, 41

SOLUTION:  

Since the measure of the longest side is 41, let c = 41, a = 9, and b = 40. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 9, 40, and 41 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

21. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = 3, and b = . Then determine whether c2 = a

2 +

b2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 3, , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

22. 

SOLUTION:  

Since the measure of the longest side is 12, let c = 12, a = 4, and b = . Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 4, , and 12 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

23. 

SOLUTION:  

Since the measure of the longest side is 14, let c = 14, a = , and b = 7. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths , 7, and 14 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

24. 8, 31.5, 32.5

SOLUTION:  

Since the measure of the longest side is 32.5, let c = 32.5, a = 8, and b = 31.5. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 8, 31.5, and 32.5 is a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number, but b and c are not whole numbers.

25. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = , and b = . Then determine whether c2 =

a2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths , , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

26. 18, 24, 30

SOLUTION:  

Since the measure of the longest side is 30, let c = 30, a = 18, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 18, 24, and 30 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

27. 36, 77, 85

SOLUTION:  

Since the measure of the longest side is 85, let c = 85, a = 36, and b = 77. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 36, 77, and 85 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

28. 17, 33, 98

SOLUTION:  Since the measure of the longest side is 98, let c = 98, a = 17, and b = 33. The length of c is greater than the sum of a and b, so this is not a triangle. 

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 17, 33, and 98 is not a triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

29. GEOMETRY  Refer to the triangle shown.

a.  What is a? b.  Find the area of the triangle.

SOLUTION:  a. Use the Pythagorean Theorem, substituting 11 for b and 23 for c.

b.

The area of the triangle is about 111.1 units2.

30. GARDENING  Khaliah wants to plant flowers in a triangular plot. She has three lengths of plastic garden edging that measure 8 feet, 15 feet, and 17 feet. Determine whether these pieces form a right triangle. Explain.

SOLUTION:  Yes; sample answer: The longest side is 17 feet so this has to be the hypotenuse.

82 + 15

2 = 17

2 so the pieces form a right triangle by the converse of the Pythagorean Theorem.

31. LADDER  Mr. Takeo is locked out of his house. The only open window is on the second floor. There is a bush along the edge of the house, so he places the neighbor’s ladder 10 feet from the house. To the nearest foot, what length of ladder does he need to reach the window?

SOLUTION:  Use the Pythagorean Theorem, substituting 10 for a and 28 for b.

He will need a 30-ft ladder to reach the window.

CCSS TOOLS  Find the length of the hypotenuse. Round to the nearest hundredth.

32. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for a and 10 for b.

33. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 7 for b.

34. DOLLHOUSE  Alonso is building a dollhouse for his sister’s birthday. The roof is 24 inches across and the slanted side is 16 inches long as shown. Find the height of the roof to the nearest tenth of an inch.

SOLUTION:  Use the Pythagorean Theorem, substituting 12 for b and 16 for c.

The height of the roof is 10.6 in.

35. GEOMETRY  Each side of a cube is 5 inches long. Find the length of a diagonal of the cube.

SOLUTION:  

Use the Pythagorean Theorem to find the diagonal of a side of the cube, substituting 5 for a and 5 for b.

Then, use the Pythagorean Theorem to find a diagonal of the cube, substituting 5 for a and  for b.

The length of a diagonal of the cube is about 8.66 in.

36. TOWN SQUARES  The largest town square in the world is Tiananmen Square in Beijing, China, covering 98 acres. a.  One square mile is 640 acres. Assuming that Tiananmen Square is a square, how many feet long is a side to the nearest foot? b.  To the nearest foot, what is the diagonal distance across Tiananmen Square?

SOLUTION:  a. First, use the conversion factor 1 square mile = 640 acres to convert the area of the square from acres to square miles.

So, 98 acres is 0.153125 square miles. Use dimensional analysis to convert this measure to square feet.  

  Next, use the formula for the area of a square to find the length of a side.

Therefore, a side of Tiananmen Square is about 2066 feet long.   b. Use the Pythagorean Theorem to find the length of the diagonal of the square, substituting 2066 for both a and b.

The diagonal distance across Tiananmen Square is about 2922 feet.

37. TRUCKS  Violeta needs to construct a ramp to roll a cart of moving boxes from her garage into the back of her truck. The truck is 6 feet from the garage. The back of the truck is 36 inches above the ground. How long does the ramp have to be?

SOLUTION:  First, rewrite 36 inches as 3 ft. Use the Pythagorean thereom, substituting 6 for a and 3 for b.

The ramp must be about 6.7 ft.

If c is the measure of the hypotenuse of a right triangle, find each missing measure. If necessary, round to the nearest hundredth.

38. a = x, b = x + 41, c = 85

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 36; b = 77

39. a = 8, b = x, c = x + 2

SOLUTION:  

b = 15; c = 17

40. a = 12, b = x − 2, c = x

SOLUTION:  

b = 35; c = 37

41. a = x, b = x + 7, c = 97

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 65; b = 72

42. a = x − 47, b = x, c = x + 2

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 16; b = 63; c = 65

43. a = x − 32, b = x − 1, c = x

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 9; b = 40; c = 41

44. GEOMETRY  A right triangle has one leg that is 8 inches shorter than the other leg. The hypotenuse is 30 inches long. Find the length of each leg.

SOLUTION:  

The length of each leg of the triangle is about 24.83 in. and about 16.83 in.

45. MULTIPLE REPRESENTATIONS In this problem, you will derive a method for finding the midpoint and length of a segment on the coordinate plane. a. Graphical Use a graph to find the lengths of the segments between (3, 2) and (8, 2) and between (4, 1) and (4, 9).Then find the midpoint of each segment. b. Logical Use what you learned in part a to write expressions for the lengths of the segments between (x1 , y) and

(x2 , y) and between (x, y1 ) and (x,  y2). What would be the midpoint of each segment?

c. Analytical Based on your results from part b, find the midpoint of the segment with endpoints at (x1, y1), and (x2,

y2).

d. Analytical Use the Pythagorean Theorem to write an expression for the distance between (x1, y1), and (x2, y2).

SOLUTION:  a.  From the graph, the length of the vertical segment is 9 – 1 or 8 units and the length of the horizontal line is 8 – 3 or 5 units.

The midpoints will be located in the middle of each segment, or the average of the coordinates. For the vertical segment, the value between 1 and 9 is 5, so the midpoint should be at (4, 5). For the horizontal segment, the value between 3 and 8 is 5.5, so the midpoint should be at (5.5, 2). b.  Distance: The length of the segment between (x1, y) and (x2, y) will be the absolute value of x1 – x2. The length

of the segment between (x, y1) and (x, y2) will be the absolute value of y1 – y2.

Midpoint: When the x-coordinates are identical, then the x-coordinate of the midpoint will also be the same value.

This is true for the y-coordinates as well. The midpoint of (x1, y) and (x2, y) is at the average of the x-coordinates

and y or at , and the midpoint of (x, y1) and (x, y2) is at .

c. When the x- and y-coordinates are both different, the midpoint should be at the average values of the coordinates,

or at .   d. Form a right triangle with the segment formed by the two points as the hypotenuse. Note that the other coordinateis (x2, y1) in the drawing. 

 

We know the Pythagorean Theorem is a2 + b

2 = c

2. We can solve this formula for c by taking the square root of

each side. So, . Now we can replace the variables with the lengths of each side. The length of

side a is x2 – x1. The length of side b is y2 – y1. The length of side c is now .

 

46. ERROR ANALYSIS  Wyatt and Dario are determining whether 36, 77, and 85 form a Pythagorean triple. Is eitherof them correct? Explain your reasoning.

SOLUTION:  Wyatt is correct. The square of the greatest value should be equal to the sum of the squares of the two smaller values.  Since this is the case, the numbers form a Pythagorean triple.

47. CCSS PERSEVERANCE  Find the value of x in the figure shown.

SOLUTION:  The figure can be separated into two right triangles. Let m represent the missing side length common to both right

triangles. From the Pythagorean Theorem, m2 = 2

2 + x

2 and 14

2 = 8

2 + m

2. Using substitution, you can find that 2

2 +

x2 = 14

2 – 8

2.

Solve for x.

48. REASONING  Provide a counterexample to the statement. Any two right triangles with the same hypotenuse have the same area.

SOLUTION:  Different lengths of a and b can produce the same value of c in the Pythagorean theorem.  

 

Sample answer: A right triangle with legs measuring 3 cm and 4 cm has a hypotenuse of 5 cm and an area of 6 cm2.

A right triangle with legs measuring 2 cm and  cm also has a hypotenuse of 5 cm, but its area is   cm2,

which is not equivalent to 6 cm2.

49. OPEN ENDED  Draw a right triangle that has a hypotenuse of  units.

SOLUTION:  Use the Pythagorean Theorem to select two side lengths for a and b with the given value of c.

 

50. WRITING IN MATH  Explain how to determine whether segments in three lengths could form a right triangle.

SOLUTION:  

From the converse of the Pythagorean Theorem, if a2 + b

2 = c

2 then a, b, and c are the lengths of the side of a right

triangle. So, check to see whether the square of the greatest number is equal to the sum of the squares of the other two numbers. Consider triangle with sides of 9, 12 and 15 and a triangle with sides of 7, 13 and 19. 

   

51. GEOMETRY  Find the missing length.

A  −17

B  −

C  

D  17

SOLUTION:  

The correct choice is C.

52. What is a solution of this equation?

F  0, 3 G  3 H  0 J  no solutions

SOLUTION:  

The correct choice is H.

53. SHORT RESPONSE  A plumber charges $40 for the first hour of each house call plus $8 for each additional half hour. If the plumber works for 4 hours, how much does he charge?

SOLUTION:  Let x = the total number of hours worked.

The plumber charges $88 for 4 hours of work.

54. Find the next term in the geometric sequence .

A  

B  

C   

D  

SOLUTION:  

The correct choice is B.

Solve each equation. Check your solution.

55. 

SOLUTION:  

Check.

56. 

SOLUTION:  

Check.

57. 

SOLUTION:  

Check.

58. 

SOLUTION:  

Check.

59. 

SOLUTION:  

Check.

60. 

SOLUTION:  

Check.

There is no real solution.

Simplify each expression.

61. 

SOLUTION:  

62. 

SOLUTION:  

63. 

SOLUTION:  

64. 

SOLUTION:  

65. 

SOLUTION:  

66. 

SOLUTION:  

Describe how the graph of each function is related to the graph of f (x) = x2.

67. g(x) = x2 − 8

SOLUTION:  

The graph of f (x) = x2 + c represents a vertical translation of the parent graph. The value of c is –8, and –8 < 0. If c

< 0, the graph of f (x) = x2 is translated  units down. Therefore, the graph of g(x) = x

2 – 8 is a translation of the

parent graph shifted down 8 units.

68. h(x) = x2

SOLUTION:  

The graph of f (x) = ax2 stretches or compresses the graph of f (x) = x

2 vertically. The value of a is , and 0 <  <

1. If 0 <  < 1, the graph of f (x) = x2 is compressed vertically. Therefore, the graph of h(x) = x

2 is the parent

graph compressed vertically.

69. h(x) = −x2 + 5

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is 5, and 5 > 0. If c > 0, the graph of f (x) = x2 is translated

 units up. Therefore, the graph of h(x) = −x2 + 5 is a translation of the parent graph shifted up 8 units and

reflected across the x-axis.

70. g(x) = (x + 10)2

SOLUTION:  

The graph of f (x) = (x – c)2 represents a horizontal translation of the parent graph. The value of c is –10, and –10 <

0. If c < 0, the graph of f (x) = (x – c)2

is translated  units left. Therefore, the graph of g(x) = (x + 10)2 is a

translation of the parent graph shifted left 10 units.

71. g(x) = −2x2

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = ax

2 stretches or

compresses the graph of f (x) = x2 vertically. The value of a is –2, and |–2| > 1. If  > 1, the graph of f (x) = x

2 is

stretched vertically. Therefore, the graph of g(x) = –2x2 is the parent graph reflected across the x-axis and stretched

vertically.

72. h(x) = −x2 −

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is , and < 0. If c < 0, the graph of f (x) = x2 is

translated  units down. Therefore, the graph of h(x) = −x2 is a translation of the parent graph shifted down

 units and reflected across the x-axis.

73. ROCK CLIMBING  While rock climbing, Damaris launches a grappling hook from a height of 6 feet with an initialupward velocity of 56 feet per second. The hook just misses the stone ledge that she wants to scale. As it falls, the hook anchors on a ledge 30 feet above the ground. How long was the hook in the air?

SOLUTION:  

A half second after she throws the hook, it is 30 feet in the air. The hook continues up, then drops back down to the height of 30 feet 3 seconds after the throw. The hook was in the air for 3 seconds.

Find each product.74. (b + 8)(b + 2)

SOLUTION:  

75. (x − 4)(x − 9)

SOLUTION:  

76. (y + 4)(y − 8)

SOLUTION:  

77. (p + 2)(p − 10)

SOLUTION:  

78. (2w − 5)(w + 7)

SOLUTION:  

79. (8d + 3)(5d + 2)

SOLUTION:  

80. BUSINESS  The amount of money spent at West Outlet Mall continues to increase. The total T(x) in millions of

dollars can be estimated by the function T(x) = 12(1.12)x, where x is the number of years after it opened in 2005.

Find the amount of sales in 2015, 2016, and 2017.

SOLUTION:  

The sales for the mall in 2015 will be about $37.27 million; in 2016 will be about $41.74 million; and in 2017 will be about $46.75 million.

Solve each proportion.

81. 

SOLUTION:  

82. 

SOLUTION:  

83. 

SOLUTION:  

84. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 4

10-5 The Pythagorean Theorem

Page 5: Find each missing length. If necessary, round to the ......Find each missing length. If necessary, round to the nearest hundredth. 62/87,21 Use the Pythagorean Theorem, substituting

Find each missing length. If necessary, round to the nearest hundredth.

1. 

SOLUTION:  Use the Pythagorean Theorem, substituting 3 for a and 4 for b.

2. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 21 for c.

3. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for b and 19 for c.

4. 

SOLUTION:  Use the Pythagorean Theorem, substituting 8 for a and 12 for b.

5. BASEBALL  A baseball diamond is a square. The distance between consecutive bases is 90 feet.

a.  How far does a catcher have to throw the ball from home plate to second base? b.  How far does a third baseman throw the ball to the first baseman from a point in the baseline 15 feet from third to second base? c.  A base runner going from first to second base is 100 feet from home plate. How far is the runner from second base?

SOLUTION:  a. Use the Pythagorean Theorem, substituting 90 for a and 90 for b.

The catcher has to throw the ball about 127 ft from home plate to second base.   b. The diagram below illustrates the throw made by the third baseman.

The length of a is 90 – 15 or 75 feet. Find the length of the throw c by using the Pythagorean Theorem, substituting 75 for a and 90 for b.

The third baseman has to throw the ball about 117 feet to the first baseman.   c. The diagram below illustrates the position of the base runner.

Use the Pythagorean Theorem to find the length of side a by substituting 90 for b and 100 for c.

So, the base runner is about 44 feet from first base to second base. Therefore, the distance the base runner is from second is about 90 – 44 or 46 feet.  

Determine whether each set of measures can be the lengths of the sides of a right triangle.6. 8, 12, 16

SOLUTION:  

Since the measure of the longest side is 16, let c = 16, a = 8, and b = 12. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 8, 12, and 16 is not a right triangle.

7. 28, 45, 53

SOLUTION:  

Since the measure of the longest side is 53, let c = 53, a = 28, and b = 45. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 28, 45, and 53 is a right triangle.

8. 7, 24, 25

SOLUTION:  

Since the measure of the longest side is 25, let c = 25, a = 7, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 7, 24, and 25 is a right triangle.

9. 15, 25, 45

SOLUTION:  

Since the measure of the longest side is 45, let c = 45, a = 15, and b = 25. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 15, 25, and 45 is not a right triangle.

Find each missing length. If necessary, round to the nearest hundredth.

10. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for a and 14 for b.

11. 

SOLUTION:  Use the Pythagorean Theorem, substituting 2 for a and 12 for c.

12. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and 20 for b.

13. 

SOLUTION:  Use the Pythagorean Theorem, substituting 9 for b and 31 for c.

14. 

SOLUTION:  Use the Pythagorean Theorem, substituting 16 for a and 26 for c.

15. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and  for b.

16. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for b and 25 for c.

17. 

SOLUTION:  

Use the Pythagorean Theorem, substituting 5 for a and  for c.

18. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for b and  for c.

19. TELEVISION  Larry is buying an entertainment stand for his television. The diagonal of his television is 42 inches. The space for the television measures 30 inches by 36 inches. Will Larry’s television fit? Explain.

SOLUTION:  Use the Pythagorean Theorem, substituting 30 for a and 36 for b.

Yes; sample answer: The diagonal of the space in the TV stand is about 46.9 inches, which is greater than the diagonal of the television, so Larry’s TV will fit.

Determine whether each set of measures can be the lengths of the sides of a right triangle. Then determine whether they form a Pythagorean triple.

20. 9, 40, 41

SOLUTION:  

Since the measure of the longest side is 41, let c = 41, a = 9, and b = 40. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 9, 40, and 41 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

21. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = 3, and b = . Then determine whether c2 = a

2 +

b2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 3, , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

22. 

SOLUTION:  

Since the measure of the longest side is 12, let c = 12, a = 4, and b = . Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 4, , and 12 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

23. 

SOLUTION:  

Since the measure of the longest side is 14, let c = 14, a = , and b = 7. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths , 7, and 14 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

24. 8, 31.5, 32.5

SOLUTION:  

Since the measure of the longest side is 32.5, let c = 32.5, a = 8, and b = 31.5. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 8, 31.5, and 32.5 is a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number, but b and c are not whole numbers.

25. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = , and b = . Then determine whether c2 =

a2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths , , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

26. 18, 24, 30

SOLUTION:  

Since the measure of the longest side is 30, let c = 30, a = 18, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 18, 24, and 30 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

27. 36, 77, 85

SOLUTION:  

Since the measure of the longest side is 85, let c = 85, a = 36, and b = 77. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 36, 77, and 85 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

28. 17, 33, 98

SOLUTION:  Since the measure of the longest side is 98, let c = 98, a = 17, and b = 33. The length of c is greater than the sum of a and b, so this is not a triangle. 

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 17, 33, and 98 is not a triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

29. GEOMETRY  Refer to the triangle shown.

a.  What is a? b.  Find the area of the triangle.

SOLUTION:  a. Use the Pythagorean Theorem, substituting 11 for b and 23 for c.

b.

The area of the triangle is about 111.1 units2.

30. GARDENING  Khaliah wants to plant flowers in a triangular plot. She has three lengths of plastic garden edging that measure 8 feet, 15 feet, and 17 feet. Determine whether these pieces form a right triangle. Explain.

SOLUTION:  Yes; sample answer: The longest side is 17 feet so this has to be the hypotenuse.

82 + 15

2 = 17

2 so the pieces form a right triangle by the converse of the Pythagorean Theorem.

31. LADDER  Mr. Takeo is locked out of his house. The only open window is on the second floor. There is a bush along the edge of the house, so he places the neighbor’s ladder 10 feet from the house. To the nearest foot, what length of ladder does he need to reach the window?

SOLUTION:  Use the Pythagorean Theorem, substituting 10 for a and 28 for b.

He will need a 30-ft ladder to reach the window.

CCSS TOOLS  Find the length of the hypotenuse. Round to the nearest hundredth.

32. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for a and 10 for b.

33. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 7 for b.

34. DOLLHOUSE  Alonso is building a dollhouse for his sister’s birthday. The roof is 24 inches across and the slanted side is 16 inches long as shown. Find the height of the roof to the nearest tenth of an inch.

SOLUTION:  Use the Pythagorean Theorem, substituting 12 for b and 16 for c.

The height of the roof is 10.6 in.

35. GEOMETRY  Each side of a cube is 5 inches long. Find the length of a diagonal of the cube.

SOLUTION:  

Use the Pythagorean Theorem to find the diagonal of a side of the cube, substituting 5 for a and 5 for b.

Then, use the Pythagorean Theorem to find a diagonal of the cube, substituting 5 for a and  for b.

The length of a diagonal of the cube is about 8.66 in.

36. TOWN SQUARES  The largest town square in the world is Tiananmen Square in Beijing, China, covering 98 acres. a.  One square mile is 640 acres. Assuming that Tiananmen Square is a square, how many feet long is a side to the nearest foot? b.  To the nearest foot, what is the diagonal distance across Tiananmen Square?

SOLUTION:  a. First, use the conversion factor 1 square mile = 640 acres to convert the area of the square from acres to square miles.

So, 98 acres is 0.153125 square miles. Use dimensional analysis to convert this measure to square feet.  

  Next, use the formula for the area of a square to find the length of a side.

Therefore, a side of Tiananmen Square is about 2066 feet long.   b. Use the Pythagorean Theorem to find the length of the diagonal of the square, substituting 2066 for both a and b.

The diagonal distance across Tiananmen Square is about 2922 feet.

37. TRUCKS  Violeta needs to construct a ramp to roll a cart of moving boxes from her garage into the back of her truck. The truck is 6 feet from the garage. The back of the truck is 36 inches above the ground. How long does the ramp have to be?

SOLUTION:  First, rewrite 36 inches as 3 ft. Use the Pythagorean thereom, substituting 6 for a and 3 for b.

The ramp must be about 6.7 ft.

If c is the measure of the hypotenuse of a right triangle, find each missing measure. If necessary, round to the nearest hundredth.

38. a = x, b = x + 41, c = 85

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 36; b = 77

39. a = 8, b = x, c = x + 2

SOLUTION:  

b = 15; c = 17

40. a = 12, b = x − 2, c = x

SOLUTION:  

b = 35; c = 37

41. a = x, b = x + 7, c = 97

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 65; b = 72

42. a = x − 47, b = x, c = x + 2

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 16; b = 63; c = 65

43. a = x − 32, b = x − 1, c = x

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 9; b = 40; c = 41

44. GEOMETRY  A right triangle has one leg that is 8 inches shorter than the other leg. The hypotenuse is 30 inches long. Find the length of each leg.

SOLUTION:  

The length of each leg of the triangle is about 24.83 in. and about 16.83 in.

45. MULTIPLE REPRESENTATIONS In this problem, you will derive a method for finding the midpoint and length of a segment on the coordinate plane. a. Graphical Use a graph to find the lengths of the segments between (3, 2) and (8, 2) and between (4, 1) and (4, 9).Then find the midpoint of each segment. b. Logical Use what you learned in part a to write expressions for the lengths of the segments between (x1 , y) and

(x2 , y) and between (x, y1 ) and (x,  y2). What would be the midpoint of each segment?

c. Analytical Based on your results from part b, find the midpoint of the segment with endpoints at (x1, y1), and (x2,

y2).

d. Analytical Use the Pythagorean Theorem to write an expression for the distance between (x1, y1), and (x2, y2).

SOLUTION:  a.  From the graph, the length of the vertical segment is 9 – 1 or 8 units and the length of the horizontal line is 8 – 3 or 5 units.

The midpoints will be located in the middle of each segment, or the average of the coordinates. For the vertical segment, the value between 1 and 9 is 5, so the midpoint should be at (4, 5). For the horizontal segment, the value between 3 and 8 is 5.5, so the midpoint should be at (5.5, 2). b.  Distance: The length of the segment between (x1, y) and (x2, y) will be the absolute value of x1 – x2. The length

of the segment between (x, y1) and (x, y2) will be the absolute value of y1 – y2.

Midpoint: When the x-coordinates are identical, then the x-coordinate of the midpoint will also be the same value.

This is true for the y-coordinates as well. The midpoint of (x1, y) and (x2, y) is at the average of the x-coordinates

and y or at , and the midpoint of (x, y1) and (x, y2) is at .

c. When the x- and y-coordinates are both different, the midpoint should be at the average values of the coordinates,

or at .   d. Form a right triangle with the segment formed by the two points as the hypotenuse. Note that the other coordinateis (x2, y1) in the drawing. 

 

We know the Pythagorean Theorem is a2 + b

2 = c

2. We can solve this formula for c by taking the square root of

each side. So, . Now we can replace the variables with the lengths of each side. The length of

side a is x2 – x1. The length of side b is y2 – y1. The length of side c is now .

 

46. ERROR ANALYSIS  Wyatt and Dario are determining whether 36, 77, and 85 form a Pythagorean triple. Is eitherof them correct? Explain your reasoning.

SOLUTION:  Wyatt is correct. The square of the greatest value should be equal to the sum of the squares of the two smaller values.  Since this is the case, the numbers form a Pythagorean triple.

47. CCSS PERSEVERANCE  Find the value of x in the figure shown.

SOLUTION:  The figure can be separated into two right triangles. Let m represent the missing side length common to both right

triangles. From the Pythagorean Theorem, m2 = 2

2 + x

2 and 14

2 = 8

2 + m

2. Using substitution, you can find that 2

2 +

x2 = 14

2 – 8

2.

Solve for x.

48. REASONING  Provide a counterexample to the statement. Any two right triangles with the same hypotenuse have the same area.

SOLUTION:  Different lengths of a and b can produce the same value of c in the Pythagorean theorem.  

 

Sample answer: A right triangle with legs measuring 3 cm and 4 cm has a hypotenuse of 5 cm and an area of 6 cm2.

A right triangle with legs measuring 2 cm and  cm also has a hypotenuse of 5 cm, but its area is   cm2,

which is not equivalent to 6 cm2.

49. OPEN ENDED  Draw a right triangle that has a hypotenuse of  units.

SOLUTION:  Use the Pythagorean Theorem to select two side lengths for a and b with the given value of c.

 

50. WRITING IN MATH  Explain how to determine whether segments in three lengths could form a right triangle.

SOLUTION:  

From the converse of the Pythagorean Theorem, if a2 + b

2 = c

2 then a, b, and c are the lengths of the side of a right

triangle. So, check to see whether the square of the greatest number is equal to the sum of the squares of the other two numbers. Consider triangle with sides of 9, 12 and 15 and a triangle with sides of 7, 13 and 19. 

   

51. GEOMETRY  Find the missing length.

A  −17

B  −

C  

D  17

SOLUTION:  

The correct choice is C.

52. What is a solution of this equation?

F  0, 3 G  3 H  0 J  no solutions

SOLUTION:  

The correct choice is H.

53. SHORT RESPONSE  A plumber charges $40 for the first hour of each house call plus $8 for each additional half hour. If the plumber works for 4 hours, how much does he charge?

SOLUTION:  Let x = the total number of hours worked.

The plumber charges $88 for 4 hours of work.

54. Find the next term in the geometric sequence .

A  

B  

C   

D  

SOLUTION:  

The correct choice is B.

Solve each equation. Check your solution.

55. 

SOLUTION:  

Check.

56. 

SOLUTION:  

Check.

57. 

SOLUTION:  

Check.

58. 

SOLUTION:  

Check.

59. 

SOLUTION:  

Check.

60. 

SOLUTION:  

Check.

There is no real solution.

Simplify each expression.

61. 

SOLUTION:  

62. 

SOLUTION:  

63. 

SOLUTION:  

64. 

SOLUTION:  

65. 

SOLUTION:  

66. 

SOLUTION:  

Describe how the graph of each function is related to the graph of f (x) = x2.

67. g(x) = x2 − 8

SOLUTION:  

The graph of f (x) = x2 + c represents a vertical translation of the parent graph. The value of c is –8, and –8 < 0. If c

< 0, the graph of f (x) = x2 is translated  units down. Therefore, the graph of g(x) = x

2 – 8 is a translation of the

parent graph shifted down 8 units.

68. h(x) = x2

SOLUTION:  

The graph of f (x) = ax2 stretches or compresses the graph of f (x) = x

2 vertically. The value of a is , and 0 <  <

1. If 0 <  < 1, the graph of f (x) = x2 is compressed vertically. Therefore, the graph of h(x) = x

2 is the parent

graph compressed vertically.

69. h(x) = −x2 + 5

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is 5, and 5 > 0. If c > 0, the graph of f (x) = x2 is translated

 units up. Therefore, the graph of h(x) = −x2 + 5 is a translation of the parent graph shifted up 8 units and

reflected across the x-axis.

70. g(x) = (x + 10)2

SOLUTION:  

The graph of f (x) = (x – c)2 represents a horizontal translation of the parent graph. The value of c is –10, and –10 <

0. If c < 0, the graph of f (x) = (x – c)2

is translated  units left. Therefore, the graph of g(x) = (x + 10)2 is a

translation of the parent graph shifted left 10 units.

71. g(x) = −2x2

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = ax

2 stretches or

compresses the graph of f (x) = x2 vertically. The value of a is –2, and |–2| > 1. If  > 1, the graph of f (x) = x

2 is

stretched vertically. Therefore, the graph of g(x) = –2x2 is the parent graph reflected across the x-axis and stretched

vertically.

72. h(x) = −x2 −

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is , and < 0. If c < 0, the graph of f (x) = x2 is

translated  units down. Therefore, the graph of h(x) = −x2 is a translation of the parent graph shifted down

 units and reflected across the x-axis.

73. ROCK CLIMBING  While rock climbing, Damaris launches a grappling hook from a height of 6 feet with an initialupward velocity of 56 feet per second. The hook just misses the stone ledge that she wants to scale. As it falls, the hook anchors on a ledge 30 feet above the ground. How long was the hook in the air?

SOLUTION:  

A half second after she throws the hook, it is 30 feet in the air. The hook continues up, then drops back down to the height of 30 feet 3 seconds after the throw. The hook was in the air for 3 seconds.

Find each product.74. (b + 8)(b + 2)

SOLUTION:  

75. (x − 4)(x − 9)

SOLUTION:  

76. (y + 4)(y − 8)

SOLUTION:  

77. (p + 2)(p − 10)

SOLUTION:  

78. (2w − 5)(w + 7)

SOLUTION:  

79. (8d + 3)(5d + 2)

SOLUTION:  

80. BUSINESS  The amount of money spent at West Outlet Mall continues to increase. The total T(x) in millions of

dollars can be estimated by the function T(x) = 12(1.12)x, where x is the number of years after it opened in 2005.

Find the amount of sales in 2015, 2016, and 2017.

SOLUTION:  

The sales for the mall in 2015 will be about $37.27 million; in 2016 will be about $41.74 million; and in 2017 will be about $46.75 million.

Solve each proportion.

81. 

SOLUTION:  

82. 

SOLUTION:  

83. 

SOLUTION:  

84. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 5

10-5 The Pythagorean Theorem

Page 6: Find each missing length. If necessary, round to the ......Find each missing length. If necessary, round to the nearest hundredth. 62/87,21 Use the Pythagorean Theorem, substituting

Find each missing length. If necessary, round to the nearest hundredth.

1. 

SOLUTION:  Use the Pythagorean Theorem, substituting 3 for a and 4 for b.

2. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 21 for c.

3. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for b and 19 for c.

4. 

SOLUTION:  Use the Pythagorean Theorem, substituting 8 for a and 12 for b.

5. BASEBALL  A baseball diamond is a square. The distance between consecutive bases is 90 feet.

a.  How far does a catcher have to throw the ball from home plate to second base? b.  How far does a third baseman throw the ball to the first baseman from a point in the baseline 15 feet from third to second base? c.  A base runner going from first to second base is 100 feet from home plate. How far is the runner from second base?

SOLUTION:  a. Use the Pythagorean Theorem, substituting 90 for a and 90 for b.

The catcher has to throw the ball about 127 ft from home plate to second base.   b. The diagram below illustrates the throw made by the third baseman.

The length of a is 90 – 15 or 75 feet. Find the length of the throw c by using the Pythagorean Theorem, substituting 75 for a and 90 for b.

The third baseman has to throw the ball about 117 feet to the first baseman.   c. The diagram below illustrates the position of the base runner.

Use the Pythagorean Theorem to find the length of side a by substituting 90 for b and 100 for c.

So, the base runner is about 44 feet from first base to second base. Therefore, the distance the base runner is from second is about 90 – 44 or 46 feet.  

Determine whether each set of measures can be the lengths of the sides of a right triangle.6. 8, 12, 16

SOLUTION:  

Since the measure of the longest side is 16, let c = 16, a = 8, and b = 12. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 8, 12, and 16 is not a right triangle.

7. 28, 45, 53

SOLUTION:  

Since the measure of the longest side is 53, let c = 53, a = 28, and b = 45. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 28, 45, and 53 is a right triangle.

8. 7, 24, 25

SOLUTION:  

Since the measure of the longest side is 25, let c = 25, a = 7, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 7, 24, and 25 is a right triangle.

9. 15, 25, 45

SOLUTION:  

Since the measure of the longest side is 45, let c = 45, a = 15, and b = 25. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 15, 25, and 45 is not a right triangle.

Find each missing length. If necessary, round to the nearest hundredth.

10. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for a and 14 for b.

11. 

SOLUTION:  Use the Pythagorean Theorem, substituting 2 for a and 12 for c.

12. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and 20 for b.

13. 

SOLUTION:  Use the Pythagorean Theorem, substituting 9 for b and 31 for c.

14. 

SOLUTION:  Use the Pythagorean Theorem, substituting 16 for a and 26 for c.

15. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and  for b.

16. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for b and 25 for c.

17. 

SOLUTION:  

Use the Pythagorean Theorem, substituting 5 for a and  for c.

18. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for b and  for c.

19. TELEVISION  Larry is buying an entertainment stand for his television. The diagonal of his television is 42 inches. The space for the television measures 30 inches by 36 inches. Will Larry’s television fit? Explain.

SOLUTION:  Use the Pythagorean Theorem, substituting 30 for a and 36 for b.

Yes; sample answer: The diagonal of the space in the TV stand is about 46.9 inches, which is greater than the diagonal of the television, so Larry’s TV will fit.

Determine whether each set of measures can be the lengths of the sides of a right triangle. Then determine whether they form a Pythagorean triple.

20. 9, 40, 41

SOLUTION:  

Since the measure of the longest side is 41, let c = 41, a = 9, and b = 40. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 9, 40, and 41 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

21. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = 3, and b = . Then determine whether c2 = a

2 +

b2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 3, , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

22. 

SOLUTION:  

Since the measure of the longest side is 12, let c = 12, a = 4, and b = . Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 4, , and 12 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

23. 

SOLUTION:  

Since the measure of the longest side is 14, let c = 14, a = , and b = 7. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths , 7, and 14 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

24. 8, 31.5, 32.5

SOLUTION:  

Since the measure of the longest side is 32.5, let c = 32.5, a = 8, and b = 31.5. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 8, 31.5, and 32.5 is a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number, but b and c are not whole numbers.

25. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = , and b = . Then determine whether c2 =

a2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths , , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

26. 18, 24, 30

SOLUTION:  

Since the measure of the longest side is 30, let c = 30, a = 18, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 18, 24, and 30 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

27. 36, 77, 85

SOLUTION:  

Since the measure of the longest side is 85, let c = 85, a = 36, and b = 77. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 36, 77, and 85 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

28. 17, 33, 98

SOLUTION:  Since the measure of the longest side is 98, let c = 98, a = 17, and b = 33. The length of c is greater than the sum of a and b, so this is not a triangle. 

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 17, 33, and 98 is not a triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

29. GEOMETRY  Refer to the triangle shown.

a.  What is a? b.  Find the area of the triangle.

SOLUTION:  a. Use the Pythagorean Theorem, substituting 11 for b and 23 for c.

b.

The area of the triangle is about 111.1 units2.

30. GARDENING  Khaliah wants to plant flowers in a triangular plot. She has three lengths of plastic garden edging that measure 8 feet, 15 feet, and 17 feet. Determine whether these pieces form a right triangle. Explain.

SOLUTION:  Yes; sample answer: The longest side is 17 feet so this has to be the hypotenuse.

82 + 15

2 = 17

2 so the pieces form a right triangle by the converse of the Pythagorean Theorem.

31. LADDER  Mr. Takeo is locked out of his house. The only open window is on the second floor. There is a bush along the edge of the house, so he places the neighbor’s ladder 10 feet from the house. To the nearest foot, what length of ladder does he need to reach the window?

SOLUTION:  Use the Pythagorean Theorem, substituting 10 for a and 28 for b.

He will need a 30-ft ladder to reach the window.

CCSS TOOLS  Find the length of the hypotenuse. Round to the nearest hundredth.

32. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for a and 10 for b.

33. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 7 for b.

34. DOLLHOUSE  Alonso is building a dollhouse for his sister’s birthday. The roof is 24 inches across and the slanted side is 16 inches long as shown. Find the height of the roof to the nearest tenth of an inch.

SOLUTION:  Use the Pythagorean Theorem, substituting 12 for b and 16 for c.

The height of the roof is 10.6 in.

35. GEOMETRY  Each side of a cube is 5 inches long. Find the length of a diagonal of the cube.

SOLUTION:  

Use the Pythagorean Theorem to find the diagonal of a side of the cube, substituting 5 for a and 5 for b.

Then, use the Pythagorean Theorem to find a diagonal of the cube, substituting 5 for a and  for b.

The length of a diagonal of the cube is about 8.66 in.

36. TOWN SQUARES  The largest town square in the world is Tiananmen Square in Beijing, China, covering 98 acres. a.  One square mile is 640 acres. Assuming that Tiananmen Square is a square, how many feet long is a side to the nearest foot? b.  To the nearest foot, what is the diagonal distance across Tiananmen Square?

SOLUTION:  a. First, use the conversion factor 1 square mile = 640 acres to convert the area of the square from acres to square miles.

So, 98 acres is 0.153125 square miles. Use dimensional analysis to convert this measure to square feet.  

  Next, use the formula for the area of a square to find the length of a side.

Therefore, a side of Tiananmen Square is about 2066 feet long.   b. Use the Pythagorean Theorem to find the length of the diagonal of the square, substituting 2066 for both a and b.

The diagonal distance across Tiananmen Square is about 2922 feet.

37. TRUCKS  Violeta needs to construct a ramp to roll a cart of moving boxes from her garage into the back of her truck. The truck is 6 feet from the garage. The back of the truck is 36 inches above the ground. How long does the ramp have to be?

SOLUTION:  First, rewrite 36 inches as 3 ft. Use the Pythagorean thereom, substituting 6 for a and 3 for b.

The ramp must be about 6.7 ft.

If c is the measure of the hypotenuse of a right triangle, find each missing measure. If necessary, round to the nearest hundredth.

38. a = x, b = x + 41, c = 85

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 36; b = 77

39. a = 8, b = x, c = x + 2

SOLUTION:  

b = 15; c = 17

40. a = 12, b = x − 2, c = x

SOLUTION:  

b = 35; c = 37

41. a = x, b = x + 7, c = 97

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 65; b = 72

42. a = x − 47, b = x, c = x + 2

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 16; b = 63; c = 65

43. a = x − 32, b = x − 1, c = x

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 9; b = 40; c = 41

44. GEOMETRY  A right triangle has one leg that is 8 inches shorter than the other leg. The hypotenuse is 30 inches long. Find the length of each leg.

SOLUTION:  

The length of each leg of the triangle is about 24.83 in. and about 16.83 in.

45. MULTIPLE REPRESENTATIONS In this problem, you will derive a method for finding the midpoint and length of a segment on the coordinate plane. a. Graphical Use a graph to find the lengths of the segments between (3, 2) and (8, 2) and between (4, 1) and (4, 9).Then find the midpoint of each segment. b. Logical Use what you learned in part a to write expressions for the lengths of the segments between (x1 , y) and

(x2 , y) and between (x, y1 ) and (x,  y2). What would be the midpoint of each segment?

c. Analytical Based on your results from part b, find the midpoint of the segment with endpoints at (x1, y1), and (x2,

y2).

d. Analytical Use the Pythagorean Theorem to write an expression for the distance between (x1, y1), and (x2, y2).

SOLUTION:  a.  From the graph, the length of the vertical segment is 9 – 1 or 8 units and the length of the horizontal line is 8 – 3 or 5 units.

The midpoints will be located in the middle of each segment, or the average of the coordinates. For the vertical segment, the value between 1 and 9 is 5, so the midpoint should be at (4, 5). For the horizontal segment, the value between 3 and 8 is 5.5, so the midpoint should be at (5.5, 2). b.  Distance: The length of the segment between (x1, y) and (x2, y) will be the absolute value of x1 – x2. The length

of the segment between (x, y1) and (x, y2) will be the absolute value of y1 – y2.

Midpoint: When the x-coordinates are identical, then the x-coordinate of the midpoint will also be the same value.

This is true for the y-coordinates as well. The midpoint of (x1, y) and (x2, y) is at the average of the x-coordinates

and y or at , and the midpoint of (x, y1) and (x, y2) is at .

c. When the x- and y-coordinates are both different, the midpoint should be at the average values of the coordinates,

or at .   d. Form a right triangle with the segment formed by the two points as the hypotenuse. Note that the other coordinateis (x2, y1) in the drawing. 

 

We know the Pythagorean Theorem is a2 + b

2 = c

2. We can solve this formula for c by taking the square root of

each side. So, . Now we can replace the variables with the lengths of each side. The length of

side a is x2 – x1. The length of side b is y2 – y1. The length of side c is now .

 

46. ERROR ANALYSIS  Wyatt and Dario are determining whether 36, 77, and 85 form a Pythagorean triple. Is eitherof them correct? Explain your reasoning.

SOLUTION:  Wyatt is correct. The square of the greatest value should be equal to the sum of the squares of the two smaller values.  Since this is the case, the numbers form a Pythagorean triple.

47. CCSS PERSEVERANCE  Find the value of x in the figure shown.

SOLUTION:  The figure can be separated into two right triangles. Let m represent the missing side length common to both right

triangles. From the Pythagorean Theorem, m2 = 2

2 + x

2 and 14

2 = 8

2 + m

2. Using substitution, you can find that 2

2 +

x2 = 14

2 – 8

2.

Solve for x.

48. REASONING  Provide a counterexample to the statement. Any two right triangles with the same hypotenuse have the same area.

SOLUTION:  Different lengths of a and b can produce the same value of c in the Pythagorean theorem.  

 

Sample answer: A right triangle with legs measuring 3 cm and 4 cm has a hypotenuse of 5 cm and an area of 6 cm2.

A right triangle with legs measuring 2 cm and  cm also has a hypotenuse of 5 cm, but its area is   cm2,

which is not equivalent to 6 cm2.

49. OPEN ENDED  Draw a right triangle that has a hypotenuse of  units.

SOLUTION:  Use the Pythagorean Theorem to select two side lengths for a and b with the given value of c.

 

50. WRITING IN MATH  Explain how to determine whether segments in three lengths could form a right triangle.

SOLUTION:  

From the converse of the Pythagorean Theorem, if a2 + b

2 = c

2 then a, b, and c are the lengths of the side of a right

triangle. So, check to see whether the square of the greatest number is equal to the sum of the squares of the other two numbers. Consider triangle with sides of 9, 12 and 15 and a triangle with sides of 7, 13 and 19. 

   

51. GEOMETRY  Find the missing length.

A  −17

B  −

C  

D  17

SOLUTION:  

The correct choice is C.

52. What is a solution of this equation?

F  0, 3 G  3 H  0 J  no solutions

SOLUTION:  

The correct choice is H.

53. SHORT RESPONSE  A plumber charges $40 for the first hour of each house call plus $8 for each additional half hour. If the plumber works for 4 hours, how much does he charge?

SOLUTION:  Let x = the total number of hours worked.

The plumber charges $88 for 4 hours of work.

54. Find the next term in the geometric sequence .

A  

B  

C   

D  

SOLUTION:  

The correct choice is B.

Solve each equation. Check your solution.

55. 

SOLUTION:  

Check.

56. 

SOLUTION:  

Check.

57. 

SOLUTION:  

Check.

58. 

SOLUTION:  

Check.

59. 

SOLUTION:  

Check.

60. 

SOLUTION:  

Check.

There is no real solution.

Simplify each expression.

61. 

SOLUTION:  

62. 

SOLUTION:  

63. 

SOLUTION:  

64. 

SOLUTION:  

65. 

SOLUTION:  

66. 

SOLUTION:  

Describe how the graph of each function is related to the graph of f (x) = x2.

67. g(x) = x2 − 8

SOLUTION:  

The graph of f (x) = x2 + c represents a vertical translation of the parent graph. The value of c is –8, and –8 < 0. If c

< 0, the graph of f (x) = x2 is translated  units down. Therefore, the graph of g(x) = x

2 – 8 is a translation of the

parent graph shifted down 8 units.

68. h(x) = x2

SOLUTION:  

The graph of f (x) = ax2 stretches or compresses the graph of f (x) = x

2 vertically. The value of a is , and 0 <  <

1. If 0 <  < 1, the graph of f (x) = x2 is compressed vertically. Therefore, the graph of h(x) = x

2 is the parent

graph compressed vertically.

69. h(x) = −x2 + 5

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is 5, and 5 > 0. If c > 0, the graph of f (x) = x2 is translated

 units up. Therefore, the graph of h(x) = −x2 + 5 is a translation of the parent graph shifted up 8 units and

reflected across the x-axis.

70. g(x) = (x + 10)2

SOLUTION:  

The graph of f (x) = (x – c)2 represents a horizontal translation of the parent graph. The value of c is –10, and –10 <

0. If c < 0, the graph of f (x) = (x – c)2

is translated  units left. Therefore, the graph of g(x) = (x + 10)2 is a

translation of the parent graph shifted left 10 units.

71. g(x) = −2x2

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = ax

2 stretches or

compresses the graph of f (x) = x2 vertically. The value of a is –2, and |–2| > 1. If  > 1, the graph of f (x) = x

2 is

stretched vertically. Therefore, the graph of g(x) = –2x2 is the parent graph reflected across the x-axis and stretched

vertically.

72. h(x) = −x2 −

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is , and < 0. If c < 0, the graph of f (x) = x2 is

translated  units down. Therefore, the graph of h(x) = −x2 is a translation of the parent graph shifted down

 units and reflected across the x-axis.

73. ROCK CLIMBING  While rock climbing, Damaris launches a grappling hook from a height of 6 feet with an initialupward velocity of 56 feet per second. The hook just misses the stone ledge that she wants to scale. As it falls, the hook anchors on a ledge 30 feet above the ground. How long was the hook in the air?

SOLUTION:  

A half second after she throws the hook, it is 30 feet in the air. The hook continues up, then drops back down to the height of 30 feet 3 seconds after the throw. The hook was in the air for 3 seconds.

Find each product.74. (b + 8)(b + 2)

SOLUTION:  

75. (x − 4)(x − 9)

SOLUTION:  

76. (y + 4)(y − 8)

SOLUTION:  

77. (p + 2)(p − 10)

SOLUTION:  

78. (2w − 5)(w + 7)

SOLUTION:  

79. (8d + 3)(5d + 2)

SOLUTION:  

80. BUSINESS  The amount of money spent at West Outlet Mall continues to increase. The total T(x) in millions of

dollars can be estimated by the function T(x) = 12(1.12)x, where x is the number of years after it opened in 2005.

Find the amount of sales in 2015, 2016, and 2017.

SOLUTION:  

The sales for the mall in 2015 will be about $37.27 million; in 2016 will be about $41.74 million; and in 2017 will be about $46.75 million.

Solve each proportion.

81. 

SOLUTION:  

82. 

SOLUTION:  

83. 

SOLUTION:  

84. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 6

10-5 The Pythagorean Theorem

Page 7: Find each missing length. If necessary, round to the ......Find each missing length. If necessary, round to the nearest hundredth. 62/87,21 Use the Pythagorean Theorem, substituting

Find each missing length. If necessary, round to the nearest hundredth.

1. 

SOLUTION:  Use the Pythagorean Theorem, substituting 3 for a and 4 for b.

2. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 21 for c.

3. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for b and 19 for c.

4. 

SOLUTION:  Use the Pythagorean Theorem, substituting 8 for a and 12 for b.

5. BASEBALL  A baseball diamond is a square. The distance between consecutive bases is 90 feet.

a.  How far does a catcher have to throw the ball from home plate to second base? b.  How far does a third baseman throw the ball to the first baseman from a point in the baseline 15 feet from third to second base? c.  A base runner going from first to second base is 100 feet from home plate. How far is the runner from second base?

SOLUTION:  a. Use the Pythagorean Theorem, substituting 90 for a and 90 for b.

The catcher has to throw the ball about 127 ft from home plate to second base.   b. The diagram below illustrates the throw made by the third baseman.

The length of a is 90 – 15 or 75 feet. Find the length of the throw c by using the Pythagorean Theorem, substituting 75 for a and 90 for b.

The third baseman has to throw the ball about 117 feet to the first baseman.   c. The diagram below illustrates the position of the base runner.

Use the Pythagorean Theorem to find the length of side a by substituting 90 for b and 100 for c.

So, the base runner is about 44 feet from first base to second base. Therefore, the distance the base runner is from second is about 90 – 44 or 46 feet.  

Determine whether each set of measures can be the lengths of the sides of a right triangle.6. 8, 12, 16

SOLUTION:  

Since the measure of the longest side is 16, let c = 16, a = 8, and b = 12. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 8, 12, and 16 is not a right triangle.

7. 28, 45, 53

SOLUTION:  

Since the measure of the longest side is 53, let c = 53, a = 28, and b = 45. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 28, 45, and 53 is a right triangle.

8. 7, 24, 25

SOLUTION:  

Since the measure of the longest side is 25, let c = 25, a = 7, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 7, 24, and 25 is a right triangle.

9. 15, 25, 45

SOLUTION:  

Since the measure of the longest side is 45, let c = 45, a = 15, and b = 25. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 15, 25, and 45 is not a right triangle.

Find each missing length. If necessary, round to the nearest hundredth.

10. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for a and 14 for b.

11. 

SOLUTION:  Use the Pythagorean Theorem, substituting 2 for a and 12 for c.

12. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and 20 for b.

13. 

SOLUTION:  Use the Pythagorean Theorem, substituting 9 for b and 31 for c.

14. 

SOLUTION:  Use the Pythagorean Theorem, substituting 16 for a and 26 for c.

15. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and  for b.

16. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for b and 25 for c.

17. 

SOLUTION:  

Use the Pythagorean Theorem, substituting 5 for a and  for c.

18. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for b and  for c.

19. TELEVISION  Larry is buying an entertainment stand for his television. The diagonal of his television is 42 inches. The space for the television measures 30 inches by 36 inches. Will Larry’s television fit? Explain.

SOLUTION:  Use the Pythagorean Theorem, substituting 30 for a and 36 for b.

Yes; sample answer: The diagonal of the space in the TV stand is about 46.9 inches, which is greater than the diagonal of the television, so Larry’s TV will fit.

Determine whether each set of measures can be the lengths of the sides of a right triangle. Then determine whether they form a Pythagorean triple.

20. 9, 40, 41

SOLUTION:  

Since the measure of the longest side is 41, let c = 41, a = 9, and b = 40. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 9, 40, and 41 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

21. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = 3, and b = . Then determine whether c2 = a

2 +

b2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 3, , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

22. 

SOLUTION:  

Since the measure of the longest side is 12, let c = 12, a = 4, and b = . Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 4, , and 12 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

23. 

SOLUTION:  

Since the measure of the longest side is 14, let c = 14, a = , and b = 7. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths , 7, and 14 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

24. 8, 31.5, 32.5

SOLUTION:  

Since the measure of the longest side is 32.5, let c = 32.5, a = 8, and b = 31.5. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 8, 31.5, and 32.5 is a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number, but b and c are not whole numbers.

25. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = , and b = . Then determine whether c2 =

a2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths , , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

26. 18, 24, 30

SOLUTION:  

Since the measure of the longest side is 30, let c = 30, a = 18, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 18, 24, and 30 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

27. 36, 77, 85

SOLUTION:  

Since the measure of the longest side is 85, let c = 85, a = 36, and b = 77. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 36, 77, and 85 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

28. 17, 33, 98

SOLUTION:  Since the measure of the longest side is 98, let c = 98, a = 17, and b = 33. The length of c is greater than the sum of a and b, so this is not a triangle. 

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 17, 33, and 98 is not a triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

29. GEOMETRY  Refer to the triangle shown.

a.  What is a? b.  Find the area of the triangle.

SOLUTION:  a. Use the Pythagorean Theorem, substituting 11 for b and 23 for c.

b.

The area of the triangle is about 111.1 units2.

30. GARDENING  Khaliah wants to plant flowers in a triangular plot. She has three lengths of plastic garden edging that measure 8 feet, 15 feet, and 17 feet. Determine whether these pieces form a right triangle. Explain.

SOLUTION:  Yes; sample answer: The longest side is 17 feet so this has to be the hypotenuse.

82 + 15

2 = 17

2 so the pieces form a right triangle by the converse of the Pythagorean Theorem.

31. LADDER  Mr. Takeo is locked out of his house. The only open window is on the second floor. There is a bush along the edge of the house, so he places the neighbor’s ladder 10 feet from the house. To the nearest foot, what length of ladder does he need to reach the window?

SOLUTION:  Use the Pythagorean Theorem, substituting 10 for a and 28 for b.

He will need a 30-ft ladder to reach the window.

CCSS TOOLS  Find the length of the hypotenuse. Round to the nearest hundredth.

32. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for a and 10 for b.

33. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 7 for b.

34. DOLLHOUSE  Alonso is building a dollhouse for his sister’s birthday. The roof is 24 inches across and the slanted side is 16 inches long as shown. Find the height of the roof to the nearest tenth of an inch.

SOLUTION:  Use the Pythagorean Theorem, substituting 12 for b and 16 for c.

The height of the roof is 10.6 in.

35. GEOMETRY  Each side of a cube is 5 inches long. Find the length of a diagonal of the cube.

SOLUTION:  

Use the Pythagorean Theorem to find the diagonal of a side of the cube, substituting 5 for a and 5 for b.

Then, use the Pythagorean Theorem to find a diagonal of the cube, substituting 5 for a and  for b.

The length of a diagonal of the cube is about 8.66 in.

36. TOWN SQUARES  The largest town square in the world is Tiananmen Square in Beijing, China, covering 98 acres. a.  One square mile is 640 acres. Assuming that Tiananmen Square is a square, how many feet long is a side to the nearest foot? b.  To the nearest foot, what is the diagonal distance across Tiananmen Square?

SOLUTION:  a. First, use the conversion factor 1 square mile = 640 acres to convert the area of the square from acres to square miles.

So, 98 acres is 0.153125 square miles. Use dimensional analysis to convert this measure to square feet.  

  Next, use the formula for the area of a square to find the length of a side.

Therefore, a side of Tiananmen Square is about 2066 feet long.   b. Use the Pythagorean Theorem to find the length of the diagonal of the square, substituting 2066 for both a and b.

The diagonal distance across Tiananmen Square is about 2922 feet.

37. TRUCKS  Violeta needs to construct a ramp to roll a cart of moving boxes from her garage into the back of her truck. The truck is 6 feet from the garage. The back of the truck is 36 inches above the ground. How long does the ramp have to be?

SOLUTION:  First, rewrite 36 inches as 3 ft. Use the Pythagorean thereom, substituting 6 for a and 3 for b.

The ramp must be about 6.7 ft.

If c is the measure of the hypotenuse of a right triangle, find each missing measure. If necessary, round to the nearest hundredth.

38. a = x, b = x + 41, c = 85

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 36; b = 77

39. a = 8, b = x, c = x + 2

SOLUTION:  

b = 15; c = 17

40. a = 12, b = x − 2, c = x

SOLUTION:  

b = 35; c = 37

41. a = x, b = x + 7, c = 97

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 65; b = 72

42. a = x − 47, b = x, c = x + 2

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 16; b = 63; c = 65

43. a = x − 32, b = x − 1, c = x

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 9; b = 40; c = 41

44. GEOMETRY  A right triangle has one leg that is 8 inches shorter than the other leg. The hypotenuse is 30 inches long. Find the length of each leg.

SOLUTION:  

The length of each leg of the triangle is about 24.83 in. and about 16.83 in.

45. MULTIPLE REPRESENTATIONS In this problem, you will derive a method for finding the midpoint and length of a segment on the coordinate plane. a. Graphical Use a graph to find the lengths of the segments between (3, 2) and (8, 2) and between (4, 1) and (4, 9).Then find the midpoint of each segment. b. Logical Use what you learned in part a to write expressions for the lengths of the segments between (x1 , y) and

(x2 , y) and between (x, y1 ) and (x,  y2). What would be the midpoint of each segment?

c. Analytical Based on your results from part b, find the midpoint of the segment with endpoints at (x1, y1), and (x2,

y2).

d. Analytical Use the Pythagorean Theorem to write an expression for the distance between (x1, y1), and (x2, y2).

SOLUTION:  a.  From the graph, the length of the vertical segment is 9 – 1 or 8 units and the length of the horizontal line is 8 – 3 or 5 units.

The midpoints will be located in the middle of each segment, or the average of the coordinates. For the vertical segment, the value between 1 and 9 is 5, so the midpoint should be at (4, 5). For the horizontal segment, the value between 3 and 8 is 5.5, so the midpoint should be at (5.5, 2). b.  Distance: The length of the segment between (x1, y) and (x2, y) will be the absolute value of x1 – x2. The length

of the segment between (x, y1) and (x, y2) will be the absolute value of y1 – y2.

Midpoint: When the x-coordinates are identical, then the x-coordinate of the midpoint will also be the same value.

This is true for the y-coordinates as well. The midpoint of (x1, y) and (x2, y) is at the average of the x-coordinates

and y or at , and the midpoint of (x, y1) and (x, y2) is at .

c. When the x- and y-coordinates are both different, the midpoint should be at the average values of the coordinates,

or at .   d. Form a right triangle with the segment formed by the two points as the hypotenuse. Note that the other coordinateis (x2, y1) in the drawing. 

 

We know the Pythagorean Theorem is a2 + b

2 = c

2. We can solve this formula for c by taking the square root of

each side. So, . Now we can replace the variables with the lengths of each side. The length of

side a is x2 – x1. The length of side b is y2 – y1. The length of side c is now .

 

46. ERROR ANALYSIS  Wyatt and Dario are determining whether 36, 77, and 85 form a Pythagorean triple. Is eitherof them correct? Explain your reasoning.

SOLUTION:  Wyatt is correct. The square of the greatest value should be equal to the sum of the squares of the two smaller values.  Since this is the case, the numbers form a Pythagorean triple.

47. CCSS PERSEVERANCE  Find the value of x in the figure shown.

SOLUTION:  The figure can be separated into two right triangles. Let m represent the missing side length common to both right

triangles. From the Pythagorean Theorem, m2 = 2

2 + x

2 and 14

2 = 8

2 + m

2. Using substitution, you can find that 2

2 +

x2 = 14

2 – 8

2.

Solve for x.

48. REASONING  Provide a counterexample to the statement. Any two right triangles with the same hypotenuse have the same area.

SOLUTION:  Different lengths of a and b can produce the same value of c in the Pythagorean theorem.  

 

Sample answer: A right triangle with legs measuring 3 cm and 4 cm has a hypotenuse of 5 cm and an area of 6 cm2.

A right triangle with legs measuring 2 cm and  cm also has a hypotenuse of 5 cm, but its area is   cm2,

which is not equivalent to 6 cm2.

49. OPEN ENDED  Draw a right triangle that has a hypotenuse of  units.

SOLUTION:  Use the Pythagorean Theorem to select two side lengths for a and b with the given value of c.

 

50. WRITING IN MATH  Explain how to determine whether segments in three lengths could form a right triangle.

SOLUTION:  

From the converse of the Pythagorean Theorem, if a2 + b

2 = c

2 then a, b, and c are the lengths of the side of a right

triangle. So, check to see whether the square of the greatest number is equal to the sum of the squares of the other two numbers. Consider triangle with sides of 9, 12 and 15 and a triangle with sides of 7, 13 and 19. 

   

51. GEOMETRY  Find the missing length.

A  −17

B  −

C  

D  17

SOLUTION:  

The correct choice is C.

52. What is a solution of this equation?

F  0, 3 G  3 H  0 J  no solutions

SOLUTION:  

The correct choice is H.

53. SHORT RESPONSE  A plumber charges $40 for the first hour of each house call plus $8 for each additional half hour. If the plumber works for 4 hours, how much does he charge?

SOLUTION:  Let x = the total number of hours worked.

The plumber charges $88 for 4 hours of work.

54. Find the next term in the geometric sequence .

A  

B  

C   

D  

SOLUTION:  

The correct choice is B.

Solve each equation. Check your solution.

55. 

SOLUTION:  

Check.

56. 

SOLUTION:  

Check.

57. 

SOLUTION:  

Check.

58. 

SOLUTION:  

Check.

59. 

SOLUTION:  

Check.

60. 

SOLUTION:  

Check.

There is no real solution.

Simplify each expression.

61. 

SOLUTION:  

62. 

SOLUTION:  

63. 

SOLUTION:  

64. 

SOLUTION:  

65. 

SOLUTION:  

66. 

SOLUTION:  

Describe how the graph of each function is related to the graph of f (x) = x2.

67. g(x) = x2 − 8

SOLUTION:  

The graph of f (x) = x2 + c represents a vertical translation of the parent graph. The value of c is –8, and –8 < 0. If c

< 0, the graph of f (x) = x2 is translated  units down. Therefore, the graph of g(x) = x

2 – 8 is a translation of the

parent graph shifted down 8 units.

68. h(x) = x2

SOLUTION:  

The graph of f (x) = ax2 stretches or compresses the graph of f (x) = x

2 vertically. The value of a is , and 0 <  <

1. If 0 <  < 1, the graph of f (x) = x2 is compressed vertically. Therefore, the graph of h(x) = x

2 is the parent

graph compressed vertically.

69. h(x) = −x2 + 5

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is 5, and 5 > 0. If c > 0, the graph of f (x) = x2 is translated

 units up. Therefore, the graph of h(x) = −x2 + 5 is a translation of the parent graph shifted up 8 units and

reflected across the x-axis.

70. g(x) = (x + 10)2

SOLUTION:  

The graph of f (x) = (x – c)2 represents a horizontal translation of the parent graph. The value of c is –10, and –10 <

0. If c < 0, the graph of f (x) = (x – c)2

is translated  units left. Therefore, the graph of g(x) = (x + 10)2 is a

translation of the parent graph shifted left 10 units.

71. g(x) = −2x2

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = ax

2 stretches or

compresses the graph of f (x) = x2 vertically. The value of a is –2, and |–2| > 1. If  > 1, the graph of f (x) = x

2 is

stretched vertically. Therefore, the graph of g(x) = –2x2 is the parent graph reflected across the x-axis and stretched

vertically.

72. h(x) = −x2 −

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is , and < 0. If c < 0, the graph of f (x) = x2 is

translated  units down. Therefore, the graph of h(x) = −x2 is a translation of the parent graph shifted down

 units and reflected across the x-axis.

73. ROCK CLIMBING  While rock climbing, Damaris launches a grappling hook from a height of 6 feet with an initialupward velocity of 56 feet per second. The hook just misses the stone ledge that she wants to scale. As it falls, the hook anchors on a ledge 30 feet above the ground. How long was the hook in the air?

SOLUTION:  

A half second after she throws the hook, it is 30 feet in the air. The hook continues up, then drops back down to the height of 30 feet 3 seconds after the throw. The hook was in the air for 3 seconds.

Find each product.74. (b + 8)(b + 2)

SOLUTION:  

75. (x − 4)(x − 9)

SOLUTION:  

76. (y + 4)(y − 8)

SOLUTION:  

77. (p + 2)(p − 10)

SOLUTION:  

78. (2w − 5)(w + 7)

SOLUTION:  

79. (8d + 3)(5d + 2)

SOLUTION:  

80. BUSINESS  The amount of money spent at West Outlet Mall continues to increase. The total T(x) in millions of

dollars can be estimated by the function T(x) = 12(1.12)x, where x is the number of years after it opened in 2005.

Find the amount of sales in 2015, 2016, and 2017.

SOLUTION:  

The sales for the mall in 2015 will be about $37.27 million; in 2016 will be about $41.74 million; and in 2017 will be about $46.75 million.

Solve each proportion.

81. 

SOLUTION:  

82. 

SOLUTION:  

83. 

SOLUTION:  

84. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 7

10-5 The Pythagorean Theorem

Page 8: Find each missing length. If necessary, round to the ......Find each missing length. If necessary, round to the nearest hundredth. 62/87,21 Use the Pythagorean Theorem, substituting

Find each missing length. If necessary, round to the nearest hundredth.

1. 

SOLUTION:  Use the Pythagorean Theorem, substituting 3 for a and 4 for b.

2. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 21 for c.

3. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for b and 19 for c.

4. 

SOLUTION:  Use the Pythagorean Theorem, substituting 8 for a and 12 for b.

5. BASEBALL  A baseball diamond is a square. The distance between consecutive bases is 90 feet.

a.  How far does a catcher have to throw the ball from home plate to second base? b.  How far does a third baseman throw the ball to the first baseman from a point in the baseline 15 feet from third to second base? c.  A base runner going from first to second base is 100 feet from home plate. How far is the runner from second base?

SOLUTION:  a. Use the Pythagorean Theorem, substituting 90 for a and 90 for b.

The catcher has to throw the ball about 127 ft from home plate to second base.   b. The diagram below illustrates the throw made by the third baseman.

The length of a is 90 – 15 or 75 feet. Find the length of the throw c by using the Pythagorean Theorem, substituting 75 for a and 90 for b.

The third baseman has to throw the ball about 117 feet to the first baseman.   c. The diagram below illustrates the position of the base runner.

Use the Pythagorean Theorem to find the length of side a by substituting 90 for b and 100 for c.

So, the base runner is about 44 feet from first base to second base. Therefore, the distance the base runner is from second is about 90 – 44 or 46 feet.  

Determine whether each set of measures can be the lengths of the sides of a right triangle.6. 8, 12, 16

SOLUTION:  

Since the measure of the longest side is 16, let c = 16, a = 8, and b = 12. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 8, 12, and 16 is not a right triangle.

7. 28, 45, 53

SOLUTION:  

Since the measure of the longest side is 53, let c = 53, a = 28, and b = 45. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 28, 45, and 53 is a right triangle.

8. 7, 24, 25

SOLUTION:  

Since the measure of the longest side is 25, let c = 25, a = 7, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 7, 24, and 25 is a right triangle.

9. 15, 25, 45

SOLUTION:  

Since the measure of the longest side is 45, let c = 45, a = 15, and b = 25. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 15, 25, and 45 is not a right triangle.

Find each missing length. If necessary, round to the nearest hundredth.

10. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for a and 14 for b.

11. 

SOLUTION:  Use the Pythagorean Theorem, substituting 2 for a and 12 for c.

12. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and 20 for b.

13. 

SOLUTION:  Use the Pythagorean Theorem, substituting 9 for b and 31 for c.

14. 

SOLUTION:  Use the Pythagorean Theorem, substituting 16 for a and 26 for c.

15. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and  for b.

16. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for b and 25 for c.

17. 

SOLUTION:  

Use the Pythagorean Theorem, substituting 5 for a and  for c.

18. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for b and  for c.

19. TELEVISION  Larry is buying an entertainment stand for his television. The diagonal of his television is 42 inches. The space for the television measures 30 inches by 36 inches. Will Larry’s television fit? Explain.

SOLUTION:  Use the Pythagorean Theorem, substituting 30 for a and 36 for b.

Yes; sample answer: The diagonal of the space in the TV stand is about 46.9 inches, which is greater than the diagonal of the television, so Larry’s TV will fit.

Determine whether each set of measures can be the lengths of the sides of a right triangle. Then determine whether they form a Pythagorean triple.

20. 9, 40, 41

SOLUTION:  

Since the measure of the longest side is 41, let c = 41, a = 9, and b = 40. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 9, 40, and 41 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

21. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = 3, and b = . Then determine whether c2 = a

2 +

b2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 3, , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

22. 

SOLUTION:  

Since the measure of the longest side is 12, let c = 12, a = 4, and b = . Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 4, , and 12 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

23. 

SOLUTION:  

Since the measure of the longest side is 14, let c = 14, a = , and b = 7. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths , 7, and 14 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

24. 8, 31.5, 32.5

SOLUTION:  

Since the measure of the longest side is 32.5, let c = 32.5, a = 8, and b = 31.5. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 8, 31.5, and 32.5 is a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number, but b and c are not whole numbers.

25. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = , and b = . Then determine whether c2 =

a2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths , , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

26. 18, 24, 30

SOLUTION:  

Since the measure of the longest side is 30, let c = 30, a = 18, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 18, 24, and 30 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

27. 36, 77, 85

SOLUTION:  

Since the measure of the longest side is 85, let c = 85, a = 36, and b = 77. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 36, 77, and 85 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

28. 17, 33, 98

SOLUTION:  Since the measure of the longest side is 98, let c = 98, a = 17, and b = 33. The length of c is greater than the sum of a and b, so this is not a triangle. 

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 17, 33, and 98 is not a triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

29. GEOMETRY  Refer to the triangle shown.

a.  What is a? b.  Find the area of the triangle.

SOLUTION:  a. Use the Pythagorean Theorem, substituting 11 for b and 23 for c.

b.

The area of the triangle is about 111.1 units2.

30. GARDENING  Khaliah wants to plant flowers in a triangular plot. She has three lengths of plastic garden edging that measure 8 feet, 15 feet, and 17 feet. Determine whether these pieces form a right triangle. Explain.

SOLUTION:  Yes; sample answer: The longest side is 17 feet so this has to be the hypotenuse.

82 + 15

2 = 17

2 so the pieces form a right triangle by the converse of the Pythagorean Theorem.

31. LADDER  Mr. Takeo is locked out of his house. The only open window is on the second floor. There is a bush along the edge of the house, so he places the neighbor’s ladder 10 feet from the house. To the nearest foot, what length of ladder does he need to reach the window?

SOLUTION:  Use the Pythagorean Theorem, substituting 10 for a and 28 for b.

He will need a 30-ft ladder to reach the window.

CCSS TOOLS  Find the length of the hypotenuse. Round to the nearest hundredth.

32. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for a and 10 for b.

33. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 7 for b.

34. DOLLHOUSE  Alonso is building a dollhouse for his sister’s birthday. The roof is 24 inches across and the slanted side is 16 inches long as shown. Find the height of the roof to the nearest tenth of an inch.

SOLUTION:  Use the Pythagorean Theorem, substituting 12 for b and 16 for c.

The height of the roof is 10.6 in.

35. GEOMETRY  Each side of a cube is 5 inches long. Find the length of a diagonal of the cube.

SOLUTION:  

Use the Pythagorean Theorem to find the diagonal of a side of the cube, substituting 5 for a and 5 for b.

Then, use the Pythagorean Theorem to find a diagonal of the cube, substituting 5 for a and  for b.

The length of a diagonal of the cube is about 8.66 in.

36. TOWN SQUARES  The largest town square in the world is Tiananmen Square in Beijing, China, covering 98 acres. a.  One square mile is 640 acres. Assuming that Tiananmen Square is a square, how many feet long is a side to the nearest foot? b.  To the nearest foot, what is the diagonal distance across Tiananmen Square?

SOLUTION:  a. First, use the conversion factor 1 square mile = 640 acres to convert the area of the square from acres to square miles.

So, 98 acres is 0.153125 square miles. Use dimensional analysis to convert this measure to square feet.  

  Next, use the formula for the area of a square to find the length of a side.

Therefore, a side of Tiananmen Square is about 2066 feet long.   b. Use the Pythagorean Theorem to find the length of the diagonal of the square, substituting 2066 for both a and b.

The diagonal distance across Tiananmen Square is about 2922 feet.

37. TRUCKS  Violeta needs to construct a ramp to roll a cart of moving boxes from her garage into the back of her truck. The truck is 6 feet from the garage. The back of the truck is 36 inches above the ground. How long does the ramp have to be?

SOLUTION:  First, rewrite 36 inches as 3 ft. Use the Pythagorean thereom, substituting 6 for a and 3 for b.

The ramp must be about 6.7 ft.

If c is the measure of the hypotenuse of a right triangle, find each missing measure. If necessary, round to the nearest hundredth.

38. a = x, b = x + 41, c = 85

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 36; b = 77

39. a = 8, b = x, c = x + 2

SOLUTION:  

b = 15; c = 17

40. a = 12, b = x − 2, c = x

SOLUTION:  

b = 35; c = 37

41. a = x, b = x + 7, c = 97

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 65; b = 72

42. a = x − 47, b = x, c = x + 2

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 16; b = 63; c = 65

43. a = x − 32, b = x − 1, c = x

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 9; b = 40; c = 41

44. GEOMETRY  A right triangle has one leg that is 8 inches shorter than the other leg. The hypotenuse is 30 inches long. Find the length of each leg.

SOLUTION:  

The length of each leg of the triangle is about 24.83 in. and about 16.83 in.

45. MULTIPLE REPRESENTATIONS In this problem, you will derive a method for finding the midpoint and length of a segment on the coordinate plane. a. Graphical Use a graph to find the lengths of the segments between (3, 2) and (8, 2) and between (4, 1) and (4, 9).Then find the midpoint of each segment. b. Logical Use what you learned in part a to write expressions for the lengths of the segments between (x1 , y) and

(x2 , y) and between (x, y1 ) and (x,  y2). What would be the midpoint of each segment?

c. Analytical Based on your results from part b, find the midpoint of the segment with endpoints at (x1, y1), and (x2,

y2).

d. Analytical Use the Pythagorean Theorem to write an expression for the distance between (x1, y1), and (x2, y2).

SOLUTION:  a.  From the graph, the length of the vertical segment is 9 – 1 or 8 units and the length of the horizontal line is 8 – 3 or 5 units.

The midpoints will be located in the middle of each segment, or the average of the coordinates. For the vertical segment, the value between 1 and 9 is 5, so the midpoint should be at (4, 5). For the horizontal segment, the value between 3 and 8 is 5.5, so the midpoint should be at (5.5, 2). b.  Distance: The length of the segment between (x1, y) and (x2, y) will be the absolute value of x1 – x2. The length

of the segment between (x, y1) and (x, y2) will be the absolute value of y1 – y2.

Midpoint: When the x-coordinates are identical, then the x-coordinate of the midpoint will also be the same value.

This is true for the y-coordinates as well. The midpoint of (x1, y) and (x2, y) is at the average of the x-coordinates

and y or at , and the midpoint of (x, y1) and (x, y2) is at .

c. When the x- and y-coordinates are both different, the midpoint should be at the average values of the coordinates,

or at .   d. Form a right triangle with the segment formed by the two points as the hypotenuse. Note that the other coordinateis (x2, y1) in the drawing. 

 

We know the Pythagorean Theorem is a2 + b

2 = c

2. We can solve this formula for c by taking the square root of

each side. So, . Now we can replace the variables with the lengths of each side. The length of

side a is x2 – x1. The length of side b is y2 – y1. The length of side c is now .

 

46. ERROR ANALYSIS  Wyatt and Dario are determining whether 36, 77, and 85 form a Pythagorean triple. Is eitherof them correct? Explain your reasoning.

SOLUTION:  Wyatt is correct. The square of the greatest value should be equal to the sum of the squares of the two smaller values.  Since this is the case, the numbers form a Pythagorean triple.

47. CCSS PERSEVERANCE  Find the value of x in the figure shown.

SOLUTION:  The figure can be separated into two right triangles. Let m represent the missing side length common to both right

triangles. From the Pythagorean Theorem, m2 = 2

2 + x

2 and 14

2 = 8

2 + m

2. Using substitution, you can find that 2

2 +

x2 = 14

2 – 8

2.

Solve for x.

48. REASONING  Provide a counterexample to the statement. Any two right triangles with the same hypotenuse have the same area.

SOLUTION:  Different lengths of a and b can produce the same value of c in the Pythagorean theorem.  

 

Sample answer: A right triangle with legs measuring 3 cm and 4 cm has a hypotenuse of 5 cm and an area of 6 cm2.

A right triangle with legs measuring 2 cm and  cm also has a hypotenuse of 5 cm, but its area is   cm2,

which is not equivalent to 6 cm2.

49. OPEN ENDED  Draw a right triangle that has a hypotenuse of  units.

SOLUTION:  Use the Pythagorean Theorem to select two side lengths for a and b with the given value of c.

 

50. WRITING IN MATH  Explain how to determine whether segments in three lengths could form a right triangle.

SOLUTION:  

From the converse of the Pythagorean Theorem, if a2 + b

2 = c

2 then a, b, and c are the lengths of the side of a right

triangle. So, check to see whether the square of the greatest number is equal to the sum of the squares of the other two numbers. Consider triangle with sides of 9, 12 and 15 and a triangle with sides of 7, 13 and 19. 

   

51. GEOMETRY  Find the missing length.

A  −17

B  −

C  

D  17

SOLUTION:  

The correct choice is C.

52. What is a solution of this equation?

F  0, 3 G  3 H  0 J  no solutions

SOLUTION:  

The correct choice is H.

53. SHORT RESPONSE  A plumber charges $40 for the first hour of each house call plus $8 for each additional half hour. If the plumber works for 4 hours, how much does he charge?

SOLUTION:  Let x = the total number of hours worked.

The plumber charges $88 for 4 hours of work.

54. Find the next term in the geometric sequence .

A  

B  

C   

D  

SOLUTION:  

The correct choice is B.

Solve each equation. Check your solution.

55. 

SOLUTION:  

Check.

56. 

SOLUTION:  

Check.

57. 

SOLUTION:  

Check.

58. 

SOLUTION:  

Check.

59. 

SOLUTION:  

Check.

60. 

SOLUTION:  

Check.

There is no real solution.

Simplify each expression.

61. 

SOLUTION:  

62. 

SOLUTION:  

63. 

SOLUTION:  

64. 

SOLUTION:  

65. 

SOLUTION:  

66. 

SOLUTION:  

Describe how the graph of each function is related to the graph of f (x) = x2.

67. g(x) = x2 − 8

SOLUTION:  

The graph of f (x) = x2 + c represents a vertical translation of the parent graph. The value of c is –8, and –8 < 0. If c

< 0, the graph of f (x) = x2 is translated  units down. Therefore, the graph of g(x) = x

2 – 8 is a translation of the

parent graph shifted down 8 units.

68. h(x) = x2

SOLUTION:  

The graph of f (x) = ax2 stretches or compresses the graph of f (x) = x

2 vertically. The value of a is , and 0 <  <

1. If 0 <  < 1, the graph of f (x) = x2 is compressed vertically. Therefore, the graph of h(x) = x

2 is the parent

graph compressed vertically.

69. h(x) = −x2 + 5

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is 5, and 5 > 0. If c > 0, the graph of f (x) = x2 is translated

 units up. Therefore, the graph of h(x) = −x2 + 5 is a translation of the parent graph shifted up 8 units and

reflected across the x-axis.

70. g(x) = (x + 10)2

SOLUTION:  

The graph of f (x) = (x – c)2 represents a horizontal translation of the parent graph. The value of c is –10, and –10 <

0. If c < 0, the graph of f (x) = (x – c)2

is translated  units left. Therefore, the graph of g(x) = (x + 10)2 is a

translation of the parent graph shifted left 10 units.

71. g(x) = −2x2

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = ax

2 stretches or

compresses the graph of f (x) = x2 vertically. The value of a is –2, and |–2| > 1. If  > 1, the graph of f (x) = x

2 is

stretched vertically. Therefore, the graph of g(x) = –2x2 is the parent graph reflected across the x-axis and stretched

vertically.

72. h(x) = −x2 −

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is , and < 0. If c < 0, the graph of f (x) = x2 is

translated  units down. Therefore, the graph of h(x) = −x2 is a translation of the parent graph shifted down

 units and reflected across the x-axis.

73. ROCK CLIMBING  While rock climbing, Damaris launches a grappling hook from a height of 6 feet with an initialupward velocity of 56 feet per second. The hook just misses the stone ledge that she wants to scale. As it falls, the hook anchors on a ledge 30 feet above the ground. How long was the hook in the air?

SOLUTION:  

A half second after she throws the hook, it is 30 feet in the air. The hook continues up, then drops back down to the height of 30 feet 3 seconds after the throw. The hook was in the air for 3 seconds.

Find each product.74. (b + 8)(b + 2)

SOLUTION:  

75. (x − 4)(x − 9)

SOLUTION:  

76. (y + 4)(y − 8)

SOLUTION:  

77. (p + 2)(p − 10)

SOLUTION:  

78. (2w − 5)(w + 7)

SOLUTION:  

79. (8d + 3)(5d + 2)

SOLUTION:  

80. BUSINESS  The amount of money spent at West Outlet Mall continues to increase. The total T(x) in millions of

dollars can be estimated by the function T(x) = 12(1.12)x, where x is the number of years after it opened in 2005.

Find the amount of sales in 2015, 2016, and 2017.

SOLUTION:  

The sales for the mall in 2015 will be about $37.27 million; in 2016 will be about $41.74 million; and in 2017 will be about $46.75 million.

Solve each proportion.

81. 

SOLUTION:  

82. 

SOLUTION:  

83. 

SOLUTION:  

84. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 8

10-5 The Pythagorean Theorem

Page 9: Find each missing length. If necessary, round to the ......Find each missing length. If necessary, round to the nearest hundredth. 62/87,21 Use the Pythagorean Theorem, substituting

Find each missing length. If necessary, round to the nearest hundredth.

1. 

SOLUTION:  Use the Pythagorean Theorem, substituting 3 for a and 4 for b.

2. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 21 for c.

3. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for b and 19 for c.

4. 

SOLUTION:  Use the Pythagorean Theorem, substituting 8 for a and 12 for b.

5. BASEBALL  A baseball diamond is a square. The distance between consecutive bases is 90 feet.

a.  How far does a catcher have to throw the ball from home plate to second base? b.  How far does a third baseman throw the ball to the first baseman from a point in the baseline 15 feet from third to second base? c.  A base runner going from first to second base is 100 feet from home plate. How far is the runner from second base?

SOLUTION:  a. Use the Pythagorean Theorem, substituting 90 for a and 90 for b.

The catcher has to throw the ball about 127 ft from home plate to second base.   b. The diagram below illustrates the throw made by the third baseman.

The length of a is 90 – 15 or 75 feet. Find the length of the throw c by using the Pythagorean Theorem, substituting 75 for a and 90 for b.

The third baseman has to throw the ball about 117 feet to the first baseman.   c. The diagram below illustrates the position of the base runner.

Use the Pythagorean Theorem to find the length of side a by substituting 90 for b and 100 for c.

So, the base runner is about 44 feet from first base to second base. Therefore, the distance the base runner is from second is about 90 – 44 or 46 feet.  

Determine whether each set of measures can be the lengths of the sides of a right triangle.6. 8, 12, 16

SOLUTION:  

Since the measure of the longest side is 16, let c = 16, a = 8, and b = 12. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 8, 12, and 16 is not a right triangle.

7. 28, 45, 53

SOLUTION:  

Since the measure of the longest side is 53, let c = 53, a = 28, and b = 45. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 28, 45, and 53 is a right triangle.

8. 7, 24, 25

SOLUTION:  

Since the measure of the longest side is 25, let c = 25, a = 7, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 7, 24, and 25 is a right triangle.

9. 15, 25, 45

SOLUTION:  

Since the measure of the longest side is 45, let c = 45, a = 15, and b = 25. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 15, 25, and 45 is not a right triangle.

Find each missing length. If necessary, round to the nearest hundredth.

10. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for a and 14 for b.

11. 

SOLUTION:  Use the Pythagorean Theorem, substituting 2 for a and 12 for c.

12. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and 20 for b.

13. 

SOLUTION:  Use the Pythagorean Theorem, substituting 9 for b and 31 for c.

14. 

SOLUTION:  Use the Pythagorean Theorem, substituting 16 for a and 26 for c.

15. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and  for b.

16. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for b and 25 for c.

17. 

SOLUTION:  

Use the Pythagorean Theorem, substituting 5 for a and  for c.

18. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for b and  for c.

19. TELEVISION  Larry is buying an entertainment stand for his television. The diagonal of his television is 42 inches. The space for the television measures 30 inches by 36 inches. Will Larry’s television fit? Explain.

SOLUTION:  Use the Pythagorean Theorem, substituting 30 for a and 36 for b.

Yes; sample answer: The diagonal of the space in the TV stand is about 46.9 inches, which is greater than the diagonal of the television, so Larry’s TV will fit.

Determine whether each set of measures can be the lengths of the sides of a right triangle. Then determine whether they form a Pythagorean triple.

20. 9, 40, 41

SOLUTION:  

Since the measure of the longest side is 41, let c = 41, a = 9, and b = 40. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 9, 40, and 41 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

21. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = 3, and b = . Then determine whether c2 = a

2 +

b2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 3, , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

22. 

SOLUTION:  

Since the measure of the longest side is 12, let c = 12, a = 4, and b = . Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 4, , and 12 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

23. 

SOLUTION:  

Since the measure of the longest side is 14, let c = 14, a = , and b = 7. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths , 7, and 14 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

24. 8, 31.5, 32.5

SOLUTION:  

Since the measure of the longest side is 32.5, let c = 32.5, a = 8, and b = 31.5. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 8, 31.5, and 32.5 is a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number, but b and c are not whole numbers.

25. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = , and b = . Then determine whether c2 =

a2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths , , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

26. 18, 24, 30

SOLUTION:  

Since the measure of the longest side is 30, let c = 30, a = 18, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 18, 24, and 30 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

27. 36, 77, 85

SOLUTION:  

Since the measure of the longest side is 85, let c = 85, a = 36, and b = 77. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 36, 77, and 85 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

28. 17, 33, 98

SOLUTION:  Since the measure of the longest side is 98, let c = 98, a = 17, and b = 33. The length of c is greater than the sum of a and b, so this is not a triangle. 

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 17, 33, and 98 is not a triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

29. GEOMETRY  Refer to the triangle shown.

a.  What is a? b.  Find the area of the triangle.

SOLUTION:  a. Use the Pythagorean Theorem, substituting 11 for b and 23 for c.

b.

The area of the triangle is about 111.1 units2.

30. GARDENING  Khaliah wants to plant flowers in a triangular plot. She has three lengths of plastic garden edging that measure 8 feet, 15 feet, and 17 feet. Determine whether these pieces form a right triangle. Explain.

SOLUTION:  Yes; sample answer: The longest side is 17 feet so this has to be the hypotenuse.

82 + 15

2 = 17

2 so the pieces form a right triangle by the converse of the Pythagorean Theorem.

31. LADDER  Mr. Takeo is locked out of his house. The only open window is on the second floor. There is a bush along the edge of the house, so he places the neighbor’s ladder 10 feet from the house. To the nearest foot, what length of ladder does he need to reach the window?

SOLUTION:  Use the Pythagorean Theorem, substituting 10 for a and 28 for b.

He will need a 30-ft ladder to reach the window.

CCSS TOOLS  Find the length of the hypotenuse. Round to the nearest hundredth.

32. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for a and 10 for b.

33. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 7 for b.

34. DOLLHOUSE  Alonso is building a dollhouse for his sister’s birthday. The roof is 24 inches across and the slanted side is 16 inches long as shown. Find the height of the roof to the nearest tenth of an inch.

SOLUTION:  Use the Pythagorean Theorem, substituting 12 for b and 16 for c.

The height of the roof is 10.6 in.

35. GEOMETRY  Each side of a cube is 5 inches long. Find the length of a diagonal of the cube.

SOLUTION:  

Use the Pythagorean Theorem to find the diagonal of a side of the cube, substituting 5 for a and 5 for b.

Then, use the Pythagorean Theorem to find a diagonal of the cube, substituting 5 for a and  for b.

The length of a diagonal of the cube is about 8.66 in.

36. TOWN SQUARES  The largest town square in the world is Tiananmen Square in Beijing, China, covering 98 acres. a.  One square mile is 640 acres. Assuming that Tiananmen Square is a square, how many feet long is a side to the nearest foot? b.  To the nearest foot, what is the diagonal distance across Tiananmen Square?

SOLUTION:  a. First, use the conversion factor 1 square mile = 640 acres to convert the area of the square from acres to square miles.

So, 98 acres is 0.153125 square miles. Use dimensional analysis to convert this measure to square feet.  

  Next, use the formula for the area of a square to find the length of a side.

Therefore, a side of Tiananmen Square is about 2066 feet long.   b. Use the Pythagorean Theorem to find the length of the diagonal of the square, substituting 2066 for both a and b.

The diagonal distance across Tiananmen Square is about 2922 feet.

37. TRUCKS  Violeta needs to construct a ramp to roll a cart of moving boxes from her garage into the back of her truck. The truck is 6 feet from the garage. The back of the truck is 36 inches above the ground. How long does the ramp have to be?

SOLUTION:  First, rewrite 36 inches as 3 ft. Use the Pythagorean thereom, substituting 6 for a and 3 for b.

The ramp must be about 6.7 ft.

If c is the measure of the hypotenuse of a right triangle, find each missing measure. If necessary, round to the nearest hundredth.

38. a = x, b = x + 41, c = 85

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 36; b = 77

39. a = 8, b = x, c = x + 2

SOLUTION:  

b = 15; c = 17

40. a = 12, b = x − 2, c = x

SOLUTION:  

b = 35; c = 37

41. a = x, b = x + 7, c = 97

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 65; b = 72

42. a = x − 47, b = x, c = x + 2

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 16; b = 63; c = 65

43. a = x − 32, b = x − 1, c = x

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 9; b = 40; c = 41

44. GEOMETRY  A right triangle has one leg that is 8 inches shorter than the other leg. The hypotenuse is 30 inches long. Find the length of each leg.

SOLUTION:  

The length of each leg of the triangle is about 24.83 in. and about 16.83 in.

45. MULTIPLE REPRESENTATIONS In this problem, you will derive a method for finding the midpoint and length of a segment on the coordinate plane. a. Graphical Use a graph to find the lengths of the segments between (3, 2) and (8, 2) and between (4, 1) and (4, 9).Then find the midpoint of each segment. b. Logical Use what you learned in part a to write expressions for the lengths of the segments between (x1 , y) and

(x2 , y) and between (x, y1 ) and (x,  y2). What would be the midpoint of each segment?

c. Analytical Based on your results from part b, find the midpoint of the segment with endpoints at (x1, y1), and (x2,

y2).

d. Analytical Use the Pythagorean Theorem to write an expression for the distance between (x1, y1), and (x2, y2).

SOLUTION:  a.  From the graph, the length of the vertical segment is 9 – 1 or 8 units and the length of the horizontal line is 8 – 3 or 5 units.

The midpoints will be located in the middle of each segment, or the average of the coordinates. For the vertical segment, the value between 1 and 9 is 5, so the midpoint should be at (4, 5). For the horizontal segment, the value between 3 and 8 is 5.5, so the midpoint should be at (5.5, 2). b.  Distance: The length of the segment between (x1, y) and (x2, y) will be the absolute value of x1 – x2. The length

of the segment between (x, y1) and (x, y2) will be the absolute value of y1 – y2.

Midpoint: When the x-coordinates are identical, then the x-coordinate of the midpoint will also be the same value.

This is true for the y-coordinates as well. The midpoint of (x1, y) and (x2, y) is at the average of the x-coordinates

and y or at , and the midpoint of (x, y1) and (x, y2) is at .

c. When the x- and y-coordinates are both different, the midpoint should be at the average values of the coordinates,

or at .   d. Form a right triangle with the segment formed by the two points as the hypotenuse. Note that the other coordinateis (x2, y1) in the drawing. 

 

We know the Pythagorean Theorem is a2 + b

2 = c

2. We can solve this formula for c by taking the square root of

each side. So, . Now we can replace the variables with the lengths of each side. The length of

side a is x2 – x1. The length of side b is y2 – y1. The length of side c is now .

 

46. ERROR ANALYSIS  Wyatt and Dario are determining whether 36, 77, and 85 form a Pythagorean triple. Is eitherof them correct? Explain your reasoning.

SOLUTION:  Wyatt is correct. The square of the greatest value should be equal to the sum of the squares of the two smaller values.  Since this is the case, the numbers form a Pythagorean triple.

47. CCSS PERSEVERANCE  Find the value of x in the figure shown.

SOLUTION:  The figure can be separated into two right triangles. Let m represent the missing side length common to both right

triangles. From the Pythagorean Theorem, m2 = 2

2 + x

2 and 14

2 = 8

2 + m

2. Using substitution, you can find that 2

2 +

x2 = 14

2 – 8

2.

Solve for x.

48. REASONING  Provide a counterexample to the statement. Any two right triangles with the same hypotenuse have the same area.

SOLUTION:  Different lengths of a and b can produce the same value of c in the Pythagorean theorem.  

 

Sample answer: A right triangle with legs measuring 3 cm and 4 cm has a hypotenuse of 5 cm and an area of 6 cm2.

A right triangle with legs measuring 2 cm and  cm also has a hypotenuse of 5 cm, but its area is   cm2,

which is not equivalent to 6 cm2.

49. OPEN ENDED  Draw a right triangle that has a hypotenuse of  units.

SOLUTION:  Use the Pythagorean Theorem to select two side lengths for a and b with the given value of c.

 

50. WRITING IN MATH  Explain how to determine whether segments in three lengths could form a right triangle.

SOLUTION:  

From the converse of the Pythagorean Theorem, if a2 + b

2 = c

2 then a, b, and c are the lengths of the side of a right

triangle. So, check to see whether the square of the greatest number is equal to the sum of the squares of the other two numbers. Consider triangle with sides of 9, 12 and 15 and a triangle with sides of 7, 13 and 19. 

   

51. GEOMETRY  Find the missing length.

A  −17

B  −

C  

D  17

SOLUTION:  

The correct choice is C.

52. What is a solution of this equation?

F  0, 3 G  3 H  0 J  no solutions

SOLUTION:  

The correct choice is H.

53. SHORT RESPONSE  A plumber charges $40 for the first hour of each house call plus $8 for each additional half hour. If the plumber works for 4 hours, how much does he charge?

SOLUTION:  Let x = the total number of hours worked.

The plumber charges $88 for 4 hours of work.

54. Find the next term in the geometric sequence .

A  

B  

C   

D  

SOLUTION:  

The correct choice is B.

Solve each equation. Check your solution.

55. 

SOLUTION:  

Check.

56. 

SOLUTION:  

Check.

57. 

SOLUTION:  

Check.

58. 

SOLUTION:  

Check.

59. 

SOLUTION:  

Check.

60. 

SOLUTION:  

Check.

There is no real solution.

Simplify each expression.

61. 

SOLUTION:  

62. 

SOLUTION:  

63. 

SOLUTION:  

64. 

SOLUTION:  

65. 

SOLUTION:  

66. 

SOLUTION:  

Describe how the graph of each function is related to the graph of f (x) = x2.

67. g(x) = x2 − 8

SOLUTION:  

The graph of f (x) = x2 + c represents a vertical translation of the parent graph. The value of c is –8, and –8 < 0. If c

< 0, the graph of f (x) = x2 is translated  units down. Therefore, the graph of g(x) = x

2 – 8 is a translation of the

parent graph shifted down 8 units.

68. h(x) = x2

SOLUTION:  

The graph of f (x) = ax2 stretches or compresses the graph of f (x) = x

2 vertically. The value of a is , and 0 <  <

1. If 0 <  < 1, the graph of f (x) = x2 is compressed vertically. Therefore, the graph of h(x) = x

2 is the parent

graph compressed vertically.

69. h(x) = −x2 + 5

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is 5, and 5 > 0. If c > 0, the graph of f (x) = x2 is translated

 units up. Therefore, the graph of h(x) = −x2 + 5 is a translation of the parent graph shifted up 8 units and

reflected across the x-axis.

70. g(x) = (x + 10)2

SOLUTION:  

The graph of f (x) = (x – c)2 represents a horizontal translation of the parent graph. The value of c is –10, and –10 <

0. If c < 0, the graph of f (x) = (x – c)2

is translated  units left. Therefore, the graph of g(x) = (x + 10)2 is a

translation of the parent graph shifted left 10 units.

71. g(x) = −2x2

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = ax

2 stretches or

compresses the graph of f (x) = x2 vertically. The value of a is –2, and |–2| > 1. If  > 1, the graph of f (x) = x

2 is

stretched vertically. Therefore, the graph of g(x) = –2x2 is the parent graph reflected across the x-axis and stretched

vertically.

72. h(x) = −x2 −

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is , and < 0. If c < 0, the graph of f (x) = x2 is

translated  units down. Therefore, the graph of h(x) = −x2 is a translation of the parent graph shifted down

 units and reflected across the x-axis.

73. ROCK CLIMBING  While rock climbing, Damaris launches a grappling hook from a height of 6 feet with an initialupward velocity of 56 feet per second. The hook just misses the stone ledge that she wants to scale. As it falls, the hook anchors on a ledge 30 feet above the ground. How long was the hook in the air?

SOLUTION:  

A half second after she throws the hook, it is 30 feet in the air. The hook continues up, then drops back down to the height of 30 feet 3 seconds after the throw. The hook was in the air for 3 seconds.

Find each product.74. (b + 8)(b + 2)

SOLUTION:  

75. (x − 4)(x − 9)

SOLUTION:  

76. (y + 4)(y − 8)

SOLUTION:  

77. (p + 2)(p − 10)

SOLUTION:  

78. (2w − 5)(w + 7)

SOLUTION:  

79. (8d + 3)(5d + 2)

SOLUTION:  

80. BUSINESS  The amount of money spent at West Outlet Mall continues to increase. The total T(x) in millions of

dollars can be estimated by the function T(x) = 12(1.12)x, where x is the number of years after it opened in 2005.

Find the amount of sales in 2015, 2016, and 2017.

SOLUTION:  

The sales for the mall in 2015 will be about $37.27 million; in 2016 will be about $41.74 million; and in 2017 will be about $46.75 million.

Solve each proportion.

81. 

SOLUTION:  

82. 

SOLUTION:  

83. 

SOLUTION:  

84. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 9

10-5 The Pythagorean Theorem

Page 10: Find each missing length. If necessary, round to the ......Find each missing length. If necessary, round to the nearest hundredth. 62/87,21 Use the Pythagorean Theorem, substituting

Find each missing length. If necessary, round to the nearest hundredth.

1. 

SOLUTION:  Use the Pythagorean Theorem, substituting 3 for a and 4 for b.

2. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 21 for c.

3. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for b and 19 for c.

4. 

SOLUTION:  Use the Pythagorean Theorem, substituting 8 for a and 12 for b.

5. BASEBALL  A baseball diamond is a square. The distance between consecutive bases is 90 feet.

a.  How far does a catcher have to throw the ball from home plate to second base? b.  How far does a third baseman throw the ball to the first baseman from a point in the baseline 15 feet from third to second base? c.  A base runner going from first to second base is 100 feet from home plate. How far is the runner from second base?

SOLUTION:  a. Use the Pythagorean Theorem, substituting 90 for a and 90 for b.

The catcher has to throw the ball about 127 ft from home plate to second base.   b. The diagram below illustrates the throw made by the third baseman.

The length of a is 90 – 15 or 75 feet. Find the length of the throw c by using the Pythagorean Theorem, substituting 75 for a and 90 for b.

The third baseman has to throw the ball about 117 feet to the first baseman.   c. The diagram below illustrates the position of the base runner.

Use the Pythagorean Theorem to find the length of side a by substituting 90 for b and 100 for c.

So, the base runner is about 44 feet from first base to second base. Therefore, the distance the base runner is from second is about 90 – 44 or 46 feet.  

Determine whether each set of measures can be the lengths of the sides of a right triangle.6. 8, 12, 16

SOLUTION:  

Since the measure of the longest side is 16, let c = 16, a = 8, and b = 12. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 8, 12, and 16 is not a right triangle.

7. 28, 45, 53

SOLUTION:  

Since the measure of the longest side is 53, let c = 53, a = 28, and b = 45. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 28, 45, and 53 is a right triangle.

8. 7, 24, 25

SOLUTION:  

Since the measure of the longest side is 25, let c = 25, a = 7, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 7, 24, and 25 is a right triangle.

9. 15, 25, 45

SOLUTION:  

Since the measure of the longest side is 45, let c = 45, a = 15, and b = 25. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 15, 25, and 45 is not a right triangle.

Find each missing length. If necessary, round to the nearest hundredth.

10. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for a and 14 for b.

11. 

SOLUTION:  Use the Pythagorean Theorem, substituting 2 for a and 12 for c.

12. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and 20 for b.

13. 

SOLUTION:  Use the Pythagorean Theorem, substituting 9 for b and 31 for c.

14. 

SOLUTION:  Use the Pythagorean Theorem, substituting 16 for a and 26 for c.

15. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and  for b.

16. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for b and 25 for c.

17. 

SOLUTION:  

Use the Pythagorean Theorem, substituting 5 for a and  for c.

18. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for b and  for c.

19. TELEVISION  Larry is buying an entertainment stand for his television. The diagonal of his television is 42 inches. The space for the television measures 30 inches by 36 inches. Will Larry’s television fit? Explain.

SOLUTION:  Use the Pythagorean Theorem, substituting 30 for a and 36 for b.

Yes; sample answer: The diagonal of the space in the TV stand is about 46.9 inches, which is greater than the diagonal of the television, so Larry’s TV will fit.

Determine whether each set of measures can be the lengths of the sides of a right triangle. Then determine whether they form a Pythagorean triple.

20. 9, 40, 41

SOLUTION:  

Since the measure of the longest side is 41, let c = 41, a = 9, and b = 40. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 9, 40, and 41 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

21. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = 3, and b = . Then determine whether c2 = a

2 +

b2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 3, , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

22. 

SOLUTION:  

Since the measure of the longest side is 12, let c = 12, a = 4, and b = . Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 4, , and 12 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

23. 

SOLUTION:  

Since the measure of the longest side is 14, let c = 14, a = , and b = 7. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths , 7, and 14 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

24. 8, 31.5, 32.5

SOLUTION:  

Since the measure of the longest side is 32.5, let c = 32.5, a = 8, and b = 31.5. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 8, 31.5, and 32.5 is a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number, but b and c are not whole numbers.

25. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = , and b = . Then determine whether c2 =

a2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths , , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

26. 18, 24, 30

SOLUTION:  

Since the measure of the longest side is 30, let c = 30, a = 18, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 18, 24, and 30 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

27. 36, 77, 85

SOLUTION:  

Since the measure of the longest side is 85, let c = 85, a = 36, and b = 77. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 36, 77, and 85 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

28. 17, 33, 98

SOLUTION:  Since the measure of the longest side is 98, let c = 98, a = 17, and b = 33. The length of c is greater than the sum of a and b, so this is not a triangle. 

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 17, 33, and 98 is not a triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

29. GEOMETRY  Refer to the triangle shown.

a.  What is a? b.  Find the area of the triangle.

SOLUTION:  a. Use the Pythagorean Theorem, substituting 11 for b and 23 for c.

b.

The area of the triangle is about 111.1 units2.

30. GARDENING  Khaliah wants to plant flowers in a triangular plot. She has three lengths of plastic garden edging that measure 8 feet, 15 feet, and 17 feet. Determine whether these pieces form a right triangle. Explain.

SOLUTION:  Yes; sample answer: The longest side is 17 feet so this has to be the hypotenuse.

82 + 15

2 = 17

2 so the pieces form a right triangle by the converse of the Pythagorean Theorem.

31. LADDER  Mr. Takeo is locked out of his house. The only open window is on the second floor. There is a bush along the edge of the house, so he places the neighbor’s ladder 10 feet from the house. To the nearest foot, what length of ladder does he need to reach the window?

SOLUTION:  Use the Pythagorean Theorem, substituting 10 for a and 28 for b.

He will need a 30-ft ladder to reach the window.

CCSS TOOLS  Find the length of the hypotenuse. Round to the nearest hundredth.

32. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for a and 10 for b.

33. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 7 for b.

34. DOLLHOUSE  Alonso is building a dollhouse for his sister’s birthday. The roof is 24 inches across and the slanted side is 16 inches long as shown. Find the height of the roof to the nearest tenth of an inch.

SOLUTION:  Use the Pythagorean Theorem, substituting 12 for b and 16 for c.

The height of the roof is 10.6 in.

35. GEOMETRY  Each side of a cube is 5 inches long. Find the length of a diagonal of the cube.

SOLUTION:  

Use the Pythagorean Theorem to find the diagonal of a side of the cube, substituting 5 for a and 5 for b.

Then, use the Pythagorean Theorem to find a diagonal of the cube, substituting 5 for a and  for b.

The length of a diagonal of the cube is about 8.66 in.

36. TOWN SQUARES  The largest town square in the world is Tiananmen Square in Beijing, China, covering 98 acres. a.  One square mile is 640 acres. Assuming that Tiananmen Square is a square, how many feet long is a side to the nearest foot? b.  To the nearest foot, what is the diagonal distance across Tiananmen Square?

SOLUTION:  a. First, use the conversion factor 1 square mile = 640 acres to convert the area of the square from acres to square miles.

So, 98 acres is 0.153125 square miles. Use dimensional analysis to convert this measure to square feet.  

  Next, use the formula for the area of a square to find the length of a side.

Therefore, a side of Tiananmen Square is about 2066 feet long.   b. Use the Pythagorean Theorem to find the length of the diagonal of the square, substituting 2066 for both a and b.

The diagonal distance across Tiananmen Square is about 2922 feet.

37. TRUCKS  Violeta needs to construct a ramp to roll a cart of moving boxes from her garage into the back of her truck. The truck is 6 feet from the garage. The back of the truck is 36 inches above the ground. How long does the ramp have to be?

SOLUTION:  First, rewrite 36 inches as 3 ft. Use the Pythagorean thereom, substituting 6 for a and 3 for b.

The ramp must be about 6.7 ft.

If c is the measure of the hypotenuse of a right triangle, find each missing measure. If necessary, round to the nearest hundredth.

38. a = x, b = x + 41, c = 85

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 36; b = 77

39. a = 8, b = x, c = x + 2

SOLUTION:  

b = 15; c = 17

40. a = 12, b = x − 2, c = x

SOLUTION:  

b = 35; c = 37

41. a = x, b = x + 7, c = 97

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 65; b = 72

42. a = x − 47, b = x, c = x + 2

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 16; b = 63; c = 65

43. a = x − 32, b = x − 1, c = x

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 9; b = 40; c = 41

44. GEOMETRY  A right triangle has one leg that is 8 inches shorter than the other leg. The hypotenuse is 30 inches long. Find the length of each leg.

SOLUTION:  

The length of each leg of the triangle is about 24.83 in. and about 16.83 in.

45. MULTIPLE REPRESENTATIONS In this problem, you will derive a method for finding the midpoint and length of a segment on the coordinate plane. a. Graphical Use a graph to find the lengths of the segments between (3, 2) and (8, 2) and between (4, 1) and (4, 9).Then find the midpoint of each segment. b. Logical Use what you learned in part a to write expressions for the lengths of the segments between (x1 , y) and

(x2 , y) and between (x, y1 ) and (x,  y2). What would be the midpoint of each segment?

c. Analytical Based on your results from part b, find the midpoint of the segment with endpoints at (x1, y1), and (x2,

y2).

d. Analytical Use the Pythagorean Theorem to write an expression for the distance between (x1, y1), and (x2, y2).

SOLUTION:  a.  From the graph, the length of the vertical segment is 9 – 1 or 8 units and the length of the horizontal line is 8 – 3 or 5 units.

The midpoints will be located in the middle of each segment, or the average of the coordinates. For the vertical segment, the value between 1 and 9 is 5, so the midpoint should be at (4, 5). For the horizontal segment, the value between 3 and 8 is 5.5, so the midpoint should be at (5.5, 2). b.  Distance: The length of the segment between (x1, y) and (x2, y) will be the absolute value of x1 – x2. The length

of the segment between (x, y1) and (x, y2) will be the absolute value of y1 – y2.

Midpoint: When the x-coordinates are identical, then the x-coordinate of the midpoint will also be the same value.

This is true for the y-coordinates as well. The midpoint of (x1, y) and (x2, y) is at the average of the x-coordinates

and y or at , and the midpoint of (x, y1) and (x, y2) is at .

c. When the x- and y-coordinates are both different, the midpoint should be at the average values of the coordinates,

or at .   d. Form a right triangle with the segment formed by the two points as the hypotenuse. Note that the other coordinateis (x2, y1) in the drawing. 

 

We know the Pythagorean Theorem is a2 + b

2 = c

2. We can solve this formula for c by taking the square root of

each side. So, . Now we can replace the variables with the lengths of each side. The length of

side a is x2 – x1. The length of side b is y2 – y1. The length of side c is now .

 

46. ERROR ANALYSIS  Wyatt and Dario are determining whether 36, 77, and 85 form a Pythagorean triple. Is eitherof them correct? Explain your reasoning.

SOLUTION:  Wyatt is correct. The square of the greatest value should be equal to the sum of the squares of the two smaller values.  Since this is the case, the numbers form a Pythagorean triple.

47. CCSS PERSEVERANCE  Find the value of x in the figure shown.

SOLUTION:  The figure can be separated into two right triangles. Let m represent the missing side length common to both right

triangles. From the Pythagorean Theorem, m2 = 2

2 + x

2 and 14

2 = 8

2 + m

2. Using substitution, you can find that 2

2 +

x2 = 14

2 – 8

2.

Solve for x.

48. REASONING  Provide a counterexample to the statement. Any two right triangles with the same hypotenuse have the same area.

SOLUTION:  Different lengths of a and b can produce the same value of c in the Pythagorean theorem.  

 

Sample answer: A right triangle with legs measuring 3 cm and 4 cm has a hypotenuse of 5 cm and an area of 6 cm2.

A right triangle with legs measuring 2 cm and  cm also has a hypotenuse of 5 cm, but its area is   cm2,

which is not equivalent to 6 cm2.

49. OPEN ENDED  Draw a right triangle that has a hypotenuse of  units.

SOLUTION:  Use the Pythagorean Theorem to select two side lengths for a and b with the given value of c.

 

50. WRITING IN MATH  Explain how to determine whether segments in three lengths could form a right triangle.

SOLUTION:  

From the converse of the Pythagorean Theorem, if a2 + b

2 = c

2 then a, b, and c are the lengths of the side of a right

triangle. So, check to see whether the square of the greatest number is equal to the sum of the squares of the other two numbers. Consider triangle with sides of 9, 12 and 15 and a triangle with sides of 7, 13 and 19. 

   

51. GEOMETRY  Find the missing length.

A  −17

B  −

C  

D  17

SOLUTION:  

The correct choice is C.

52. What is a solution of this equation?

F  0, 3 G  3 H  0 J  no solutions

SOLUTION:  

The correct choice is H.

53. SHORT RESPONSE  A plumber charges $40 for the first hour of each house call plus $8 for each additional half hour. If the plumber works for 4 hours, how much does he charge?

SOLUTION:  Let x = the total number of hours worked.

The plumber charges $88 for 4 hours of work.

54. Find the next term in the geometric sequence .

A  

B  

C   

D  

SOLUTION:  

The correct choice is B.

Solve each equation. Check your solution.

55. 

SOLUTION:  

Check.

56. 

SOLUTION:  

Check.

57. 

SOLUTION:  

Check.

58. 

SOLUTION:  

Check.

59. 

SOLUTION:  

Check.

60. 

SOLUTION:  

Check.

There is no real solution.

Simplify each expression.

61. 

SOLUTION:  

62. 

SOLUTION:  

63. 

SOLUTION:  

64. 

SOLUTION:  

65. 

SOLUTION:  

66. 

SOLUTION:  

Describe how the graph of each function is related to the graph of f (x) = x2.

67. g(x) = x2 − 8

SOLUTION:  

The graph of f (x) = x2 + c represents a vertical translation of the parent graph. The value of c is –8, and –8 < 0. If c

< 0, the graph of f (x) = x2 is translated  units down. Therefore, the graph of g(x) = x

2 – 8 is a translation of the

parent graph shifted down 8 units.

68. h(x) = x2

SOLUTION:  

The graph of f (x) = ax2 stretches or compresses the graph of f (x) = x

2 vertically. The value of a is , and 0 <  <

1. If 0 <  < 1, the graph of f (x) = x2 is compressed vertically. Therefore, the graph of h(x) = x

2 is the parent

graph compressed vertically.

69. h(x) = −x2 + 5

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is 5, and 5 > 0. If c > 0, the graph of f (x) = x2 is translated

 units up. Therefore, the graph of h(x) = −x2 + 5 is a translation of the parent graph shifted up 8 units and

reflected across the x-axis.

70. g(x) = (x + 10)2

SOLUTION:  

The graph of f (x) = (x – c)2 represents a horizontal translation of the parent graph. The value of c is –10, and –10 <

0. If c < 0, the graph of f (x) = (x – c)2

is translated  units left. Therefore, the graph of g(x) = (x + 10)2 is a

translation of the parent graph shifted left 10 units.

71. g(x) = −2x2

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = ax

2 stretches or

compresses the graph of f (x) = x2 vertically. The value of a is –2, and |–2| > 1. If  > 1, the graph of f (x) = x

2 is

stretched vertically. Therefore, the graph of g(x) = –2x2 is the parent graph reflected across the x-axis and stretched

vertically.

72. h(x) = −x2 −

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is , and < 0. If c < 0, the graph of f (x) = x2 is

translated  units down. Therefore, the graph of h(x) = −x2 is a translation of the parent graph shifted down

 units and reflected across the x-axis.

73. ROCK CLIMBING  While rock climbing, Damaris launches a grappling hook from a height of 6 feet with an initialupward velocity of 56 feet per second. The hook just misses the stone ledge that she wants to scale. As it falls, the hook anchors on a ledge 30 feet above the ground. How long was the hook in the air?

SOLUTION:  

A half second after she throws the hook, it is 30 feet in the air. The hook continues up, then drops back down to the height of 30 feet 3 seconds after the throw. The hook was in the air for 3 seconds.

Find each product.74. (b + 8)(b + 2)

SOLUTION:  

75. (x − 4)(x − 9)

SOLUTION:  

76. (y + 4)(y − 8)

SOLUTION:  

77. (p + 2)(p − 10)

SOLUTION:  

78. (2w − 5)(w + 7)

SOLUTION:  

79. (8d + 3)(5d + 2)

SOLUTION:  

80. BUSINESS  The amount of money spent at West Outlet Mall continues to increase. The total T(x) in millions of

dollars can be estimated by the function T(x) = 12(1.12)x, where x is the number of years after it opened in 2005.

Find the amount of sales in 2015, 2016, and 2017.

SOLUTION:  

The sales for the mall in 2015 will be about $37.27 million; in 2016 will be about $41.74 million; and in 2017 will be about $46.75 million.

Solve each proportion.

81. 

SOLUTION:  

82. 

SOLUTION:  

83. 

SOLUTION:  

84. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 10

10-5 The Pythagorean Theorem

Page 11: Find each missing length. If necessary, round to the ......Find each missing length. If necessary, round to the nearest hundredth. 62/87,21 Use the Pythagorean Theorem, substituting

Find each missing length. If necessary, round to the nearest hundredth.

1. 

SOLUTION:  Use the Pythagorean Theorem, substituting 3 for a and 4 for b.

2. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 21 for c.

3. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for b and 19 for c.

4. 

SOLUTION:  Use the Pythagorean Theorem, substituting 8 for a and 12 for b.

5. BASEBALL  A baseball diamond is a square. The distance between consecutive bases is 90 feet.

a.  How far does a catcher have to throw the ball from home plate to second base? b.  How far does a third baseman throw the ball to the first baseman from a point in the baseline 15 feet from third to second base? c.  A base runner going from first to second base is 100 feet from home plate. How far is the runner from second base?

SOLUTION:  a. Use the Pythagorean Theorem, substituting 90 for a and 90 for b.

The catcher has to throw the ball about 127 ft from home plate to second base.   b. The diagram below illustrates the throw made by the third baseman.

The length of a is 90 – 15 or 75 feet. Find the length of the throw c by using the Pythagorean Theorem, substituting 75 for a and 90 for b.

The third baseman has to throw the ball about 117 feet to the first baseman.   c. The diagram below illustrates the position of the base runner.

Use the Pythagorean Theorem to find the length of side a by substituting 90 for b and 100 for c.

So, the base runner is about 44 feet from first base to second base. Therefore, the distance the base runner is from second is about 90 – 44 or 46 feet.  

Determine whether each set of measures can be the lengths of the sides of a right triangle.6. 8, 12, 16

SOLUTION:  

Since the measure of the longest side is 16, let c = 16, a = 8, and b = 12. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 8, 12, and 16 is not a right triangle.

7. 28, 45, 53

SOLUTION:  

Since the measure of the longest side is 53, let c = 53, a = 28, and b = 45. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 28, 45, and 53 is a right triangle.

8. 7, 24, 25

SOLUTION:  

Since the measure of the longest side is 25, let c = 25, a = 7, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 7, 24, and 25 is a right triangle.

9. 15, 25, 45

SOLUTION:  

Since the measure of the longest side is 45, let c = 45, a = 15, and b = 25. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 15, 25, and 45 is not a right triangle.

Find each missing length. If necessary, round to the nearest hundredth.

10. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for a and 14 for b.

11. 

SOLUTION:  Use the Pythagorean Theorem, substituting 2 for a and 12 for c.

12. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and 20 for b.

13. 

SOLUTION:  Use the Pythagorean Theorem, substituting 9 for b and 31 for c.

14. 

SOLUTION:  Use the Pythagorean Theorem, substituting 16 for a and 26 for c.

15. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and  for b.

16. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for b and 25 for c.

17. 

SOLUTION:  

Use the Pythagorean Theorem, substituting 5 for a and  for c.

18. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for b and  for c.

19. TELEVISION  Larry is buying an entertainment stand for his television. The diagonal of his television is 42 inches. The space for the television measures 30 inches by 36 inches. Will Larry’s television fit? Explain.

SOLUTION:  Use the Pythagorean Theorem, substituting 30 for a and 36 for b.

Yes; sample answer: The diagonal of the space in the TV stand is about 46.9 inches, which is greater than the diagonal of the television, so Larry’s TV will fit.

Determine whether each set of measures can be the lengths of the sides of a right triangle. Then determine whether they form a Pythagorean triple.

20. 9, 40, 41

SOLUTION:  

Since the measure of the longest side is 41, let c = 41, a = 9, and b = 40. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 9, 40, and 41 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

21. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = 3, and b = . Then determine whether c2 = a

2 +

b2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 3, , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

22. 

SOLUTION:  

Since the measure of the longest side is 12, let c = 12, a = 4, and b = . Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 4, , and 12 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

23. 

SOLUTION:  

Since the measure of the longest side is 14, let c = 14, a = , and b = 7. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths , 7, and 14 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

24. 8, 31.5, 32.5

SOLUTION:  

Since the measure of the longest side is 32.5, let c = 32.5, a = 8, and b = 31.5. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 8, 31.5, and 32.5 is a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number, but b and c are not whole numbers.

25. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = , and b = . Then determine whether c2 =

a2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths , , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

26. 18, 24, 30

SOLUTION:  

Since the measure of the longest side is 30, let c = 30, a = 18, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 18, 24, and 30 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

27. 36, 77, 85

SOLUTION:  

Since the measure of the longest side is 85, let c = 85, a = 36, and b = 77. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 36, 77, and 85 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

28. 17, 33, 98

SOLUTION:  Since the measure of the longest side is 98, let c = 98, a = 17, and b = 33. The length of c is greater than the sum of a and b, so this is not a triangle. 

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 17, 33, and 98 is not a triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

29. GEOMETRY  Refer to the triangle shown.

a.  What is a? b.  Find the area of the triangle.

SOLUTION:  a. Use the Pythagorean Theorem, substituting 11 for b and 23 for c.

b.

The area of the triangle is about 111.1 units2.

30. GARDENING  Khaliah wants to plant flowers in a triangular plot. She has three lengths of plastic garden edging that measure 8 feet, 15 feet, and 17 feet. Determine whether these pieces form a right triangle. Explain.

SOLUTION:  Yes; sample answer: The longest side is 17 feet so this has to be the hypotenuse.

82 + 15

2 = 17

2 so the pieces form a right triangle by the converse of the Pythagorean Theorem.

31. LADDER  Mr. Takeo is locked out of his house. The only open window is on the second floor. There is a bush along the edge of the house, so he places the neighbor’s ladder 10 feet from the house. To the nearest foot, what length of ladder does he need to reach the window?

SOLUTION:  Use the Pythagorean Theorem, substituting 10 for a and 28 for b.

He will need a 30-ft ladder to reach the window.

CCSS TOOLS  Find the length of the hypotenuse. Round to the nearest hundredth.

32. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for a and 10 for b.

33. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 7 for b.

34. DOLLHOUSE  Alonso is building a dollhouse for his sister’s birthday. The roof is 24 inches across and the slanted side is 16 inches long as shown. Find the height of the roof to the nearest tenth of an inch.

SOLUTION:  Use the Pythagorean Theorem, substituting 12 for b and 16 for c.

The height of the roof is 10.6 in.

35. GEOMETRY  Each side of a cube is 5 inches long. Find the length of a diagonal of the cube.

SOLUTION:  

Use the Pythagorean Theorem to find the diagonal of a side of the cube, substituting 5 for a and 5 for b.

Then, use the Pythagorean Theorem to find a diagonal of the cube, substituting 5 for a and  for b.

The length of a diagonal of the cube is about 8.66 in.

36. TOWN SQUARES  The largest town square in the world is Tiananmen Square in Beijing, China, covering 98 acres. a.  One square mile is 640 acres. Assuming that Tiananmen Square is a square, how many feet long is a side to the nearest foot? b.  To the nearest foot, what is the diagonal distance across Tiananmen Square?

SOLUTION:  a. First, use the conversion factor 1 square mile = 640 acres to convert the area of the square from acres to square miles.

So, 98 acres is 0.153125 square miles. Use dimensional analysis to convert this measure to square feet.  

  Next, use the formula for the area of a square to find the length of a side.

Therefore, a side of Tiananmen Square is about 2066 feet long.   b. Use the Pythagorean Theorem to find the length of the diagonal of the square, substituting 2066 for both a and b.

The diagonal distance across Tiananmen Square is about 2922 feet.

37. TRUCKS  Violeta needs to construct a ramp to roll a cart of moving boxes from her garage into the back of her truck. The truck is 6 feet from the garage. The back of the truck is 36 inches above the ground. How long does the ramp have to be?

SOLUTION:  First, rewrite 36 inches as 3 ft. Use the Pythagorean thereom, substituting 6 for a and 3 for b.

The ramp must be about 6.7 ft.

If c is the measure of the hypotenuse of a right triangle, find each missing measure. If necessary, round to the nearest hundredth.

38. a = x, b = x + 41, c = 85

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 36; b = 77

39. a = 8, b = x, c = x + 2

SOLUTION:  

b = 15; c = 17

40. a = 12, b = x − 2, c = x

SOLUTION:  

b = 35; c = 37

41. a = x, b = x + 7, c = 97

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 65; b = 72

42. a = x − 47, b = x, c = x + 2

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 16; b = 63; c = 65

43. a = x − 32, b = x − 1, c = x

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 9; b = 40; c = 41

44. GEOMETRY  A right triangle has one leg that is 8 inches shorter than the other leg. The hypotenuse is 30 inches long. Find the length of each leg.

SOLUTION:  

The length of each leg of the triangle is about 24.83 in. and about 16.83 in.

45. MULTIPLE REPRESENTATIONS In this problem, you will derive a method for finding the midpoint and length of a segment on the coordinate plane. a. Graphical Use a graph to find the lengths of the segments between (3, 2) and (8, 2) and between (4, 1) and (4, 9).Then find the midpoint of each segment. b. Logical Use what you learned in part a to write expressions for the lengths of the segments between (x1 , y) and

(x2 , y) and between (x, y1 ) and (x,  y2). What would be the midpoint of each segment?

c. Analytical Based on your results from part b, find the midpoint of the segment with endpoints at (x1, y1), and (x2,

y2).

d. Analytical Use the Pythagorean Theorem to write an expression for the distance between (x1, y1), and (x2, y2).

SOLUTION:  a.  From the graph, the length of the vertical segment is 9 – 1 or 8 units and the length of the horizontal line is 8 – 3 or 5 units.

The midpoints will be located in the middle of each segment, or the average of the coordinates. For the vertical segment, the value between 1 and 9 is 5, so the midpoint should be at (4, 5). For the horizontal segment, the value between 3 and 8 is 5.5, so the midpoint should be at (5.5, 2). b.  Distance: The length of the segment between (x1, y) and (x2, y) will be the absolute value of x1 – x2. The length

of the segment between (x, y1) and (x, y2) will be the absolute value of y1 – y2.

Midpoint: When the x-coordinates are identical, then the x-coordinate of the midpoint will also be the same value.

This is true for the y-coordinates as well. The midpoint of (x1, y) and (x2, y) is at the average of the x-coordinates

and y or at , and the midpoint of (x, y1) and (x, y2) is at .

c. When the x- and y-coordinates are both different, the midpoint should be at the average values of the coordinates,

or at .   d. Form a right triangle with the segment formed by the two points as the hypotenuse. Note that the other coordinateis (x2, y1) in the drawing. 

 

We know the Pythagorean Theorem is a2 + b

2 = c

2. We can solve this formula for c by taking the square root of

each side. So, . Now we can replace the variables with the lengths of each side. The length of

side a is x2 – x1. The length of side b is y2 – y1. The length of side c is now .

 

46. ERROR ANALYSIS  Wyatt and Dario are determining whether 36, 77, and 85 form a Pythagorean triple. Is eitherof them correct? Explain your reasoning.

SOLUTION:  Wyatt is correct. The square of the greatest value should be equal to the sum of the squares of the two smaller values.  Since this is the case, the numbers form a Pythagorean triple.

47. CCSS PERSEVERANCE  Find the value of x in the figure shown.

SOLUTION:  The figure can be separated into two right triangles. Let m represent the missing side length common to both right

triangles. From the Pythagorean Theorem, m2 = 2

2 + x

2 and 14

2 = 8

2 + m

2. Using substitution, you can find that 2

2 +

x2 = 14

2 – 8

2.

Solve for x.

48. REASONING  Provide a counterexample to the statement. Any two right triangles with the same hypotenuse have the same area.

SOLUTION:  Different lengths of a and b can produce the same value of c in the Pythagorean theorem.  

 

Sample answer: A right triangle with legs measuring 3 cm and 4 cm has a hypotenuse of 5 cm and an area of 6 cm2.

A right triangle with legs measuring 2 cm and  cm also has a hypotenuse of 5 cm, but its area is   cm2,

which is not equivalent to 6 cm2.

49. OPEN ENDED  Draw a right triangle that has a hypotenuse of  units.

SOLUTION:  Use the Pythagorean Theorem to select two side lengths for a and b with the given value of c.

 

50. WRITING IN MATH  Explain how to determine whether segments in three lengths could form a right triangle.

SOLUTION:  

From the converse of the Pythagorean Theorem, if a2 + b

2 = c

2 then a, b, and c are the lengths of the side of a right

triangle. So, check to see whether the square of the greatest number is equal to the sum of the squares of the other two numbers. Consider triangle with sides of 9, 12 and 15 and a triangle with sides of 7, 13 and 19. 

   

51. GEOMETRY  Find the missing length.

A  −17

B  −

C  

D  17

SOLUTION:  

The correct choice is C.

52. What is a solution of this equation?

F  0, 3 G  3 H  0 J  no solutions

SOLUTION:  

The correct choice is H.

53. SHORT RESPONSE  A plumber charges $40 for the first hour of each house call plus $8 for each additional half hour. If the plumber works for 4 hours, how much does he charge?

SOLUTION:  Let x = the total number of hours worked.

The plumber charges $88 for 4 hours of work.

54. Find the next term in the geometric sequence .

A  

B  

C   

D  

SOLUTION:  

The correct choice is B.

Solve each equation. Check your solution.

55. 

SOLUTION:  

Check.

56. 

SOLUTION:  

Check.

57. 

SOLUTION:  

Check.

58. 

SOLUTION:  

Check.

59. 

SOLUTION:  

Check.

60. 

SOLUTION:  

Check.

There is no real solution.

Simplify each expression.

61. 

SOLUTION:  

62. 

SOLUTION:  

63. 

SOLUTION:  

64. 

SOLUTION:  

65. 

SOLUTION:  

66. 

SOLUTION:  

Describe how the graph of each function is related to the graph of f (x) = x2.

67. g(x) = x2 − 8

SOLUTION:  

The graph of f (x) = x2 + c represents a vertical translation of the parent graph. The value of c is –8, and –8 < 0. If c

< 0, the graph of f (x) = x2 is translated  units down. Therefore, the graph of g(x) = x

2 – 8 is a translation of the

parent graph shifted down 8 units.

68. h(x) = x2

SOLUTION:  

The graph of f (x) = ax2 stretches or compresses the graph of f (x) = x

2 vertically. The value of a is , and 0 <  <

1. If 0 <  < 1, the graph of f (x) = x2 is compressed vertically. Therefore, the graph of h(x) = x

2 is the parent

graph compressed vertically.

69. h(x) = −x2 + 5

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is 5, and 5 > 0. If c > 0, the graph of f (x) = x2 is translated

 units up. Therefore, the graph of h(x) = −x2 + 5 is a translation of the parent graph shifted up 8 units and

reflected across the x-axis.

70. g(x) = (x + 10)2

SOLUTION:  

The graph of f (x) = (x – c)2 represents a horizontal translation of the parent graph. The value of c is –10, and –10 <

0. If c < 0, the graph of f (x) = (x – c)2

is translated  units left. Therefore, the graph of g(x) = (x + 10)2 is a

translation of the parent graph shifted left 10 units.

71. g(x) = −2x2

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = ax

2 stretches or

compresses the graph of f (x) = x2 vertically. The value of a is –2, and |–2| > 1. If  > 1, the graph of f (x) = x

2 is

stretched vertically. Therefore, the graph of g(x) = –2x2 is the parent graph reflected across the x-axis and stretched

vertically.

72. h(x) = −x2 −

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is , and < 0. If c < 0, the graph of f (x) = x2 is

translated  units down. Therefore, the graph of h(x) = −x2 is a translation of the parent graph shifted down

 units and reflected across the x-axis.

73. ROCK CLIMBING  While rock climbing, Damaris launches a grappling hook from a height of 6 feet with an initialupward velocity of 56 feet per second. The hook just misses the stone ledge that she wants to scale. As it falls, the hook anchors on a ledge 30 feet above the ground. How long was the hook in the air?

SOLUTION:  

A half second after she throws the hook, it is 30 feet in the air. The hook continues up, then drops back down to the height of 30 feet 3 seconds after the throw. The hook was in the air for 3 seconds.

Find each product.74. (b + 8)(b + 2)

SOLUTION:  

75. (x − 4)(x − 9)

SOLUTION:  

76. (y + 4)(y − 8)

SOLUTION:  

77. (p + 2)(p − 10)

SOLUTION:  

78. (2w − 5)(w + 7)

SOLUTION:  

79. (8d + 3)(5d + 2)

SOLUTION:  

80. BUSINESS  The amount of money spent at West Outlet Mall continues to increase. The total T(x) in millions of

dollars can be estimated by the function T(x) = 12(1.12)x, where x is the number of years after it opened in 2005.

Find the amount of sales in 2015, 2016, and 2017.

SOLUTION:  

The sales for the mall in 2015 will be about $37.27 million; in 2016 will be about $41.74 million; and in 2017 will be about $46.75 million.

Solve each proportion.

81. 

SOLUTION:  

82. 

SOLUTION:  

83. 

SOLUTION:  

84. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 11

10-5 The Pythagorean Theorem

Page 12: Find each missing length. If necessary, round to the ......Find each missing length. If necessary, round to the nearest hundredth. 62/87,21 Use the Pythagorean Theorem, substituting

Find each missing length. If necessary, round to the nearest hundredth.

1. 

SOLUTION:  Use the Pythagorean Theorem, substituting 3 for a and 4 for b.

2. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 21 for c.

3. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for b and 19 for c.

4. 

SOLUTION:  Use the Pythagorean Theorem, substituting 8 for a and 12 for b.

5. BASEBALL  A baseball diamond is a square. The distance between consecutive bases is 90 feet.

a.  How far does a catcher have to throw the ball from home plate to second base? b.  How far does a third baseman throw the ball to the first baseman from a point in the baseline 15 feet from third to second base? c.  A base runner going from first to second base is 100 feet from home plate. How far is the runner from second base?

SOLUTION:  a. Use the Pythagorean Theorem, substituting 90 for a and 90 for b.

The catcher has to throw the ball about 127 ft from home plate to second base.   b. The diagram below illustrates the throw made by the third baseman.

The length of a is 90 – 15 or 75 feet. Find the length of the throw c by using the Pythagorean Theorem, substituting 75 for a and 90 for b.

The third baseman has to throw the ball about 117 feet to the first baseman.   c. The diagram below illustrates the position of the base runner.

Use the Pythagorean Theorem to find the length of side a by substituting 90 for b and 100 for c.

So, the base runner is about 44 feet from first base to second base. Therefore, the distance the base runner is from second is about 90 – 44 or 46 feet.  

Determine whether each set of measures can be the lengths of the sides of a right triangle.6. 8, 12, 16

SOLUTION:  

Since the measure of the longest side is 16, let c = 16, a = 8, and b = 12. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 8, 12, and 16 is not a right triangle.

7. 28, 45, 53

SOLUTION:  

Since the measure of the longest side is 53, let c = 53, a = 28, and b = 45. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 28, 45, and 53 is a right triangle.

8. 7, 24, 25

SOLUTION:  

Since the measure of the longest side is 25, let c = 25, a = 7, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 7, 24, and 25 is a right triangle.

9. 15, 25, 45

SOLUTION:  

Since the measure of the longest side is 45, let c = 45, a = 15, and b = 25. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 15, 25, and 45 is not a right triangle.

Find each missing length. If necessary, round to the nearest hundredth.

10. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for a and 14 for b.

11. 

SOLUTION:  Use the Pythagorean Theorem, substituting 2 for a and 12 for c.

12. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and 20 for b.

13. 

SOLUTION:  Use the Pythagorean Theorem, substituting 9 for b and 31 for c.

14. 

SOLUTION:  Use the Pythagorean Theorem, substituting 16 for a and 26 for c.

15. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and  for b.

16. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for b and 25 for c.

17. 

SOLUTION:  

Use the Pythagorean Theorem, substituting 5 for a and  for c.

18. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for b and  for c.

19. TELEVISION  Larry is buying an entertainment stand for his television. The diagonal of his television is 42 inches. The space for the television measures 30 inches by 36 inches. Will Larry’s television fit? Explain.

SOLUTION:  Use the Pythagorean Theorem, substituting 30 for a and 36 for b.

Yes; sample answer: The diagonal of the space in the TV stand is about 46.9 inches, which is greater than the diagonal of the television, so Larry’s TV will fit.

Determine whether each set of measures can be the lengths of the sides of a right triangle. Then determine whether they form a Pythagorean triple.

20. 9, 40, 41

SOLUTION:  

Since the measure of the longest side is 41, let c = 41, a = 9, and b = 40. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 9, 40, and 41 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

21. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = 3, and b = . Then determine whether c2 = a

2 +

b2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 3, , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

22. 

SOLUTION:  

Since the measure of the longest side is 12, let c = 12, a = 4, and b = . Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 4, , and 12 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

23. 

SOLUTION:  

Since the measure of the longest side is 14, let c = 14, a = , and b = 7. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths , 7, and 14 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

24. 8, 31.5, 32.5

SOLUTION:  

Since the measure of the longest side is 32.5, let c = 32.5, a = 8, and b = 31.5. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 8, 31.5, and 32.5 is a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number, but b and c are not whole numbers.

25. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = , and b = . Then determine whether c2 =

a2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths , , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

26. 18, 24, 30

SOLUTION:  

Since the measure of the longest side is 30, let c = 30, a = 18, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 18, 24, and 30 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

27. 36, 77, 85

SOLUTION:  

Since the measure of the longest side is 85, let c = 85, a = 36, and b = 77. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 36, 77, and 85 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

28. 17, 33, 98

SOLUTION:  Since the measure of the longest side is 98, let c = 98, a = 17, and b = 33. The length of c is greater than the sum of a and b, so this is not a triangle. 

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 17, 33, and 98 is not a triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

29. GEOMETRY  Refer to the triangle shown.

a.  What is a? b.  Find the area of the triangle.

SOLUTION:  a. Use the Pythagorean Theorem, substituting 11 for b and 23 for c.

b.

The area of the triangle is about 111.1 units2.

30. GARDENING  Khaliah wants to plant flowers in a triangular plot. She has three lengths of plastic garden edging that measure 8 feet, 15 feet, and 17 feet. Determine whether these pieces form a right triangle. Explain.

SOLUTION:  Yes; sample answer: The longest side is 17 feet so this has to be the hypotenuse.

82 + 15

2 = 17

2 so the pieces form a right triangle by the converse of the Pythagorean Theorem.

31. LADDER  Mr. Takeo is locked out of his house. The only open window is on the second floor. There is a bush along the edge of the house, so he places the neighbor’s ladder 10 feet from the house. To the nearest foot, what length of ladder does he need to reach the window?

SOLUTION:  Use the Pythagorean Theorem, substituting 10 for a and 28 for b.

He will need a 30-ft ladder to reach the window.

CCSS TOOLS  Find the length of the hypotenuse. Round to the nearest hundredth.

32. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for a and 10 for b.

33. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 7 for b.

34. DOLLHOUSE  Alonso is building a dollhouse for his sister’s birthday. The roof is 24 inches across and the slanted side is 16 inches long as shown. Find the height of the roof to the nearest tenth of an inch.

SOLUTION:  Use the Pythagorean Theorem, substituting 12 for b and 16 for c.

The height of the roof is 10.6 in.

35. GEOMETRY  Each side of a cube is 5 inches long. Find the length of a diagonal of the cube.

SOLUTION:  

Use the Pythagorean Theorem to find the diagonal of a side of the cube, substituting 5 for a and 5 for b.

Then, use the Pythagorean Theorem to find a diagonal of the cube, substituting 5 for a and  for b.

The length of a diagonal of the cube is about 8.66 in.

36. TOWN SQUARES  The largest town square in the world is Tiananmen Square in Beijing, China, covering 98 acres. a.  One square mile is 640 acres. Assuming that Tiananmen Square is a square, how many feet long is a side to the nearest foot? b.  To the nearest foot, what is the diagonal distance across Tiananmen Square?

SOLUTION:  a. First, use the conversion factor 1 square mile = 640 acres to convert the area of the square from acres to square miles.

So, 98 acres is 0.153125 square miles. Use dimensional analysis to convert this measure to square feet.  

  Next, use the formula for the area of a square to find the length of a side.

Therefore, a side of Tiananmen Square is about 2066 feet long.   b. Use the Pythagorean Theorem to find the length of the diagonal of the square, substituting 2066 for both a and b.

The diagonal distance across Tiananmen Square is about 2922 feet.

37. TRUCKS  Violeta needs to construct a ramp to roll a cart of moving boxes from her garage into the back of her truck. The truck is 6 feet from the garage. The back of the truck is 36 inches above the ground. How long does the ramp have to be?

SOLUTION:  First, rewrite 36 inches as 3 ft. Use the Pythagorean thereom, substituting 6 for a and 3 for b.

The ramp must be about 6.7 ft.

If c is the measure of the hypotenuse of a right triangle, find each missing measure. If necessary, round to the nearest hundredth.

38. a = x, b = x + 41, c = 85

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 36; b = 77

39. a = 8, b = x, c = x + 2

SOLUTION:  

b = 15; c = 17

40. a = 12, b = x − 2, c = x

SOLUTION:  

b = 35; c = 37

41. a = x, b = x + 7, c = 97

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 65; b = 72

42. a = x − 47, b = x, c = x + 2

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 16; b = 63; c = 65

43. a = x − 32, b = x − 1, c = x

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 9; b = 40; c = 41

44. GEOMETRY  A right triangle has one leg that is 8 inches shorter than the other leg. The hypotenuse is 30 inches long. Find the length of each leg.

SOLUTION:  

The length of each leg of the triangle is about 24.83 in. and about 16.83 in.

45. MULTIPLE REPRESENTATIONS In this problem, you will derive a method for finding the midpoint and length of a segment on the coordinate plane. a. Graphical Use a graph to find the lengths of the segments between (3, 2) and (8, 2) and between (4, 1) and (4, 9).Then find the midpoint of each segment. b. Logical Use what you learned in part a to write expressions for the lengths of the segments between (x1 , y) and

(x2 , y) and between (x, y1 ) and (x,  y2). What would be the midpoint of each segment?

c. Analytical Based on your results from part b, find the midpoint of the segment with endpoints at (x1, y1), and (x2,

y2).

d. Analytical Use the Pythagorean Theorem to write an expression for the distance between (x1, y1), and (x2, y2).

SOLUTION:  a.  From the graph, the length of the vertical segment is 9 – 1 or 8 units and the length of the horizontal line is 8 – 3 or 5 units.

The midpoints will be located in the middle of each segment, or the average of the coordinates. For the vertical segment, the value between 1 and 9 is 5, so the midpoint should be at (4, 5). For the horizontal segment, the value between 3 and 8 is 5.5, so the midpoint should be at (5.5, 2). b.  Distance: The length of the segment between (x1, y) and (x2, y) will be the absolute value of x1 – x2. The length

of the segment between (x, y1) and (x, y2) will be the absolute value of y1 – y2.

Midpoint: When the x-coordinates are identical, then the x-coordinate of the midpoint will also be the same value.

This is true for the y-coordinates as well. The midpoint of (x1, y) and (x2, y) is at the average of the x-coordinates

and y or at , and the midpoint of (x, y1) and (x, y2) is at .

c. When the x- and y-coordinates are both different, the midpoint should be at the average values of the coordinates,

or at .   d. Form a right triangle with the segment formed by the two points as the hypotenuse. Note that the other coordinateis (x2, y1) in the drawing. 

 

We know the Pythagorean Theorem is a2 + b

2 = c

2. We can solve this formula for c by taking the square root of

each side. So, . Now we can replace the variables with the lengths of each side. The length of

side a is x2 – x1. The length of side b is y2 – y1. The length of side c is now .

 

46. ERROR ANALYSIS  Wyatt and Dario are determining whether 36, 77, and 85 form a Pythagorean triple. Is eitherof them correct? Explain your reasoning.

SOLUTION:  Wyatt is correct. The square of the greatest value should be equal to the sum of the squares of the two smaller values.  Since this is the case, the numbers form a Pythagorean triple.

47. CCSS PERSEVERANCE  Find the value of x in the figure shown.

SOLUTION:  The figure can be separated into two right triangles. Let m represent the missing side length common to both right

triangles. From the Pythagorean Theorem, m2 = 2

2 + x

2 and 14

2 = 8

2 + m

2. Using substitution, you can find that 2

2 +

x2 = 14

2 – 8

2.

Solve for x.

48. REASONING  Provide a counterexample to the statement. Any two right triangles with the same hypotenuse have the same area.

SOLUTION:  Different lengths of a and b can produce the same value of c in the Pythagorean theorem.  

 

Sample answer: A right triangle with legs measuring 3 cm and 4 cm has a hypotenuse of 5 cm and an area of 6 cm2.

A right triangle with legs measuring 2 cm and  cm also has a hypotenuse of 5 cm, but its area is   cm2,

which is not equivalent to 6 cm2.

49. OPEN ENDED  Draw a right triangle that has a hypotenuse of  units.

SOLUTION:  Use the Pythagorean Theorem to select two side lengths for a and b with the given value of c.

 

50. WRITING IN MATH  Explain how to determine whether segments in three lengths could form a right triangle.

SOLUTION:  

From the converse of the Pythagorean Theorem, if a2 + b

2 = c

2 then a, b, and c are the lengths of the side of a right

triangle. So, check to see whether the square of the greatest number is equal to the sum of the squares of the other two numbers. Consider triangle with sides of 9, 12 and 15 and a triangle with sides of 7, 13 and 19. 

   

51. GEOMETRY  Find the missing length.

A  −17

B  −

C  

D  17

SOLUTION:  

The correct choice is C.

52. What is a solution of this equation?

F  0, 3 G  3 H  0 J  no solutions

SOLUTION:  

The correct choice is H.

53. SHORT RESPONSE  A plumber charges $40 for the first hour of each house call plus $8 for each additional half hour. If the plumber works for 4 hours, how much does he charge?

SOLUTION:  Let x = the total number of hours worked.

The plumber charges $88 for 4 hours of work.

54. Find the next term in the geometric sequence .

A  

B  

C   

D  

SOLUTION:  

The correct choice is B.

Solve each equation. Check your solution.

55. 

SOLUTION:  

Check.

56. 

SOLUTION:  

Check.

57. 

SOLUTION:  

Check.

58. 

SOLUTION:  

Check.

59. 

SOLUTION:  

Check.

60. 

SOLUTION:  

Check.

There is no real solution.

Simplify each expression.

61. 

SOLUTION:  

62. 

SOLUTION:  

63. 

SOLUTION:  

64. 

SOLUTION:  

65. 

SOLUTION:  

66. 

SOLUTION:  

Describe how the graph of each function is related to the graph of f (x) = x2.

67. g(x) = x2 − 8

SOLUTION:  

The graph of f (x) = x2 + c represents a vertical translation of the parent graph. The value of c is –8, and –8 < 0. If c

< 0, the graph of f (x) = x2 is translated  units down. Therefore, the graph of g(x) = x

2 – 8 is a translation of the

parent graph shifted down 8 units.

68. h(x) = x2

SOLUTION:  

The graph of f (x) = ax2 stretches or compresses the graph of f (x) = x

2 vertically. The value of a is , and 0 <  <

1. If 0 <  < 1, the graph of f (x) = x2 is compressed vertically. Therefore, the graph of h(x) = x

2 is the parent

graph compressed vertically.

69. h(x) = −x2 + 5

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is 5, and 5 > 0. If c > 0, the graph of f (x) = x2 is translated

 units up. Therefore, the graph of h(x) = −x2 + 5 is a translation of the parent graph shifted up 8 units and

reflected across the x-axis.

70. g(x) = (x + 10)2

SOLUTION:  

The graph of f (x) = (x – c)2 represents a horizontal translation of the parent graph. The value of c is –10, and –10 <

0. If c < 0, the graph of f (x) = (x – c)2

is translated  units left. Therefore, the graph of g(x) = (x + 10)2 is a

translation of the parent graph shifted left 10 units.

71. g(x) = −2x2

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = ax

2 stretches or

compresses the graph of f (x) = x2 vertically. The value of a is –2, and |–2| > 1. If  > 1, the graph of f (x) = x

2 is

stretched vertically. Therefore, the graph of g(x) = –2x2 is the parent graph reflected across the x-axis and stretched

vertically.

72. h(x) = −x2 −

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is , and < 0. If c < 0, the graph of f (x) = x2 is

translated  units down. Therefore, the graph of h(x) = −x2 is a translation of the parent graph shifted down

 units and reflected across the x-axis.

73. ROCK CLIMBING  While rock climbing, Damaris launches a grappling hook from a height of 6 feet with an initialupward velocity of 56 feet per second. The hook just misses the stone ledge that she wants to scale. As it falls, the hook anchors on a ledge 30 feet above the ground. How long was the hook in the air?

SOLUTION:  

A half second after she throws the hook, it is 30 feet in the air. The hook continues up, then drops back down to the height of 30 feet 3 seconds after the throw. The hook was in the air for 3 seconds.

Find each product.74. (b + 8)(b + 2)

SOLUTION:  

75. (x − 4)(x − 9)

SOLUTION:  

76. (y + 4)(y − 8)

SOLUTION:  

77. (p + 2)(p − 10)

SOLUTION:  

78. (2w − 5)(w + 7)

SOLUTION:  

79. (8d + 3)(5d + 2)

SOLUTION:  

80. BUSINESS  The amount of money spent at West Outlet Mall continues to increase. The total T(x) in millions of

dollars can be estimated by the function T(x) = 12(1.12)x, where x is the number of years after it opened in 2005.

Find the amount of sales in 2015, 2016, and 2017.

SOLUTION:  

The sales for the mall in 2015 will be about $37.27 million; in 2016 will be about $41.74 million; and in 2017 will be about $46.75 million.

Solve each proportion.

81. 

SOLUTION:  

82. 

SOLUTION:  

83. 

SOLUTION:  

84. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 12

10-5 The Pythagorean Theorem

Page 13: Find each missing length. If necessary, round to the ......Find each missing length. If necessary, round to the nearest hundredth. 62/87,21 Use the Pythagorean Theorem, substituting

Find each missing length. If necessary, round to the nearest hundredth.

1. 

SOLUTION:  Use the Pythagorean Theorem, substituting 3 for a and 4 for b.

2. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 21 for c.

3. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for b and 19 for c.

4. 

SOLUTION:  Use the Pythagorean Theorem, substituting 8 for a and 12 for b.

5. BASEBALL  A baseball diamond is a square. The distance between consecutive bases is 90 feet.

a.  How far does a catcher have to throw the ball from home plate to second base? b.  How far does a third baseman throw the ball to the first baseman from a point in the baseline 15 feet from third to second base? c.  A base runner going from first to second base is 100 feet from home plate. How far is the runner from second base?

SOLUTION:  a. Use the Pythagorean Theorem, substituting 90 for a and 90 for b.

The catcher has to throw the ball about 127 ft from home plate to second base.   b. The diagram below illustrates the throw made by the third baseman.

The length of a is 90 – 15 or 75 feet. Find the length of the throw c by using the Pythagorean Theorem, substituting 75 for a and 90 for b.

The third baseman has to throw the ball about 117 feet to the first baseman.   c. The diagram below illustrates the position of the base runner.

Use the Pythagorean Theorem to find the length of side a by substituting 90 for b and 100 for c.

So, the base runner is about 44 feet from first base to second base. Therefore, the distance the base runner is from second is about 90 – 44 or 46 feet.  

Determine whether each set of measures can be the lengths of the sides of a right triangle.6. 8, 12, 16

SOLUTION:  

Since the measure of the longest side is 16, let c = 16, a = 8, and b = 12. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 8, 12, and 16 is not a right triangle.

7. 28, 45, 53

SOLUTION:  

Since the measure of the longest side is 53, let c = 53, a = 28, and b = 45. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 28, 45, and 53 is a right triangle.

8. 7, 24, 25

SOLUTION:  

Since the measure of the longest side is 25, let c = 25, a = 7, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 7, 24, and 25 is a right triangle.

9. 15, 25, 45

SOLUTION:  

Since the measure of the longest side is 45, let c = 45, a = 15, and b = 25. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 15, 25, and 45 is not a right triangle.

Find each missing length. If necessary, round to the nearest hundredth.

10. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for a and 14 for b.

11. 

SOLUTION:  Use the Pythagorean Theorem, substituting 2 for a and 12 for c.

12. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and 20 for b.

13. 

SOLUTION:  Use the Pythagorean Theorem, substituting 9 for b and 31 for c.

14. 

SOLUTION:  Use the Pythagorean Theorem, substituting 16 for a and 26 for c.

15. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and  for b.

16. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for b and 25 for c.

17. 

SOLUTION:  

Use the Pythagorean Theorem, substituting 5 for a and  for c.

18. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for b and  for c.

19. TELEVISION  Larry is buying an entertainment stand for his television. The diagonal of his television is 42 inches. The space for the television measures 30 inches by 36 inches. Will Larry’s television fit? Explain.

SOLUTION:  Use the Pythagorean Theorem, substituting 30 for a and 36 for b.

Yes; sample answer: The diagonal of the space in the TV stand is about 46.9 inches, which is greater than the diagonal of the television, so Larry’s TV will fit.

Determine whether each set of measures can be the lengths of the sides of a right triangle. Then determine whether they form a Pythagorean triple.

20. 9, 40, 41

SOLUTION:  

Since the measure of the longest side is 41, let c = 41, a = 9, and b = 40. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 9, 40, and 41 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

21. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = 3, and b = . Then determine whether c2 = a

2 +

b2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 3, , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

22. 

SOLUTION:  

Since the measure of the longest side is 12, let c = 12, a = 4, and b = . Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 4, , and 12 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

23. 

SOLUTION:  

Since the measure of the longest side is 14, let c = 14, a = , and b = 7. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths , 7, and 14 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

24. 8, 31.5, 32.5

SOLUTION:  

Since the measure of the longest side is 32.5, let c = 32.5, a = 8, and b = 31.5. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 8, 31.5, and 32.5 is a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number, but b and c are not whole numbers.

25. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = , and b = . Then determine whether c2 =

a2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths , , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

26. 18, 24, 30

SOLUTION:  

Since the measure of the longest side is 30, let c = 30, a = 18, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 18, 24, and 30 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

27. 36, 77, 85

SOLUTION:  

Since the measure of the longest side is 85, let c = 85, a = 36, and b = 77. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 36, 77, and 85 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

28. 17, 33, 98

SOLUTION:  Since the measure of the longest side is 98, let c = 98, a = 17, and b = 33. The length of c is greater than the sum of a and b, so this is not a triangle. 

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 17, 33, and 98 is not a triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

29. GEOMETRY  Refer to the triangle shown.

a.  What is a? b.  Find the area of the triangle.

SOLUTION:  a. Use the Pythagorean Theorem, substituting 11 for b and 23 for c.

b.

The area of the triangle is about 111.1 units2.

30. GARDENING  Khaliah wants to plant flowers in a triangular plot. She has three lengths of plastic garden edging that measure 8 feet, 15 feet, and 17 feet. Determine whether these pieces form a right triangle. Explain.

SOLUTION:  Yes; sample answer: The longest side is 17 feet so this has to be the hypotenuse.

82 + 15

2 = 17

2 so the pieces form a right triangle by the converse of the Pythagorean Theorem.

31. LADDER  Mr. Takeo is locked out of his house. The only open window is on the second floor. There is a bush along the edge of the house, so he places the neighbor’s ladder 10 feet from the house. To the nearest foot, what length of ladder does he need to reach the window?

SOLUTION:  Use the Pythagorean Theorem, substituting 10 for a and 28 for b.

He will need a 30-ft ladder to reach the window.

CCSS TOOLS  Find the length of the hypotenuse. Round to the nearest hundredth.

32. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for a and 10 for b.

33. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 7 for b.

34. DOLLHOUSE  Alonso is building a dollhouse for his sister’s birthday. The roof is 24 inches across and the slanted side is 16 inches long as shown. Find the height of the roof to the nearest tenth of an inch.

SOLUTION:  Use the Pythagorean Theorem, substituting 12 for b and 16 for c.

The height of the roof is 10.6 in.

35. GEOMETRY  Each side of a cube is 5 inches long. Find the length of a diagonal of the cube.

SOLUTION:  

Use the Pythagorean Theorem to find the diagonal of a side of the cube, substituting 5 for a and 5 for b.

Then, use the Pythagorean Theorem to find a diagonal of the cube, substituting 5 for a and  for b.

The length of a diagonal of the cube is about 8.66 in.

36. TOWN SQUARES  The largest town square in the world is Tiananmen Square in Beijing, China, covering 98 acres. a.  One square mile is 640 acres. Assuming that Tiananmen Square is a square, how many feet long is a side to the nearest foot? b.  To the nearest foot, what is the diagonal distance across Tiananmen Square?

SOLUTION:  a. First, use the conversion factor 1 square mile = 640 acres to convert the area of the square from acres to square miles.

So, 98 acres is 0.153125 square miles. Use dimensional analysis to convert this measure to square feet.  

  Next, use the formula for the area of a square to find the length of a side.

Therefore, a side of Tiananmen Square is about 2066 feet long.   b. Use the Pythagorean Theorem to find the length of the diagonal of the square, substituting 2066 for both a and b.

The diagonal distance across Tiananmen Square is about 2922 feet.

37. TRUCKS  Violeta needs to construct a ramp to roll a cart of moving boxes from her garage into the back of her truck. The truck is 6 feet from the garage. The back of the truck is 36 inches above the ground. How long does the ramp have to be?

SOLUTION:  First, rewrite 36 inches as 3 ft. Use the Pythagorean thereom, substituting 6 for a and 3 for b.

The ramp must be about 6.7 ft.

If c is the measure of the hypotenuse of a right triangle, find each missing measure. If necessary, round to the nearest hundredth.

38. a = x, b = x + 41, c = 85

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 36; b = 77

39. a = 8, b = x, c = x + 2

SOLUTION:  

b = 15; c = 17

40. a = 12, b = x − 2, c = x

SOLUTION:  

b = 35; c = 37

41. a = x, b = x + 7, c = 97

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 65; b = 72

42. a = x − 47, b = x, c = x + 2

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 16; b = 63; c = 65

43. a = x − 32, b = x − 1, c = x

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 9; b = 40; c = 41

44. GEOMETRY  A right triangle has one leg that is 8 inches shorter than the other leg. The hypotenuse is 30 inches long. Find the length of each leg.

SOLUTION:  

The length of each leg of the triangle is about 24.83 in. and about 16.83 in.

45. MULTIPLE REPRESENTATIONS In this problem, you will derive a method for finding the midpoint and length of a segment on the coordinate plane. a. Graphical Use a graph to find the lengths of the segments between (3, 2) and (8, 2) and between (4, 1) and (4, 9).Then find the midpoint of each segment. b. Logical Use what you learned in part a to write expressions for the lengths of the segments between (x1 , y) and

(x2 , y) and between (x, y1 ) and (x,  y2). What would be the midpoint of each segment?

c. Analytical Based on your results from part b, find the midpoint of the segment with endpoints at (x1, y1), and (x2,

y2).

d. Analytical Use the Pythagorean Theorem to write an expression for the distance between (x1, y1), and (x2, y2).

SOLUTION:  a.  From the graph, the length of the vertical segment is 9 – 1 or 8 units and the length of the horizontal line is 8 – 3 or 5 units.

The midpoints will be located in the middle of each segment, or the average of the coordinates. For the vertical segment, the value between 1 and 9 is 5, so the midpoint should be at (4, 5). For the horizontal segment, the value between 3 and 8 is 5.5, so the midpoint should be at (5.5, 2). b.  Distance: The length of the segment between (x1, y) and (x2, y) will be the absolute value of x1 – x2. The length

of the segment between (x, y1) and (x, y2) will be the absolute value of y1 – y2.

Midpoint: When the x-coordinates are identical, then the x-coordinate of the midpoint will also be the same value.

This is true for the y-coordinates as well. The midpoint of (x1, y) and (x2, y) is at the average of the x-coordinates

and y or at , and the midpoint of (x, y1) and (x, y2) is at .

c. When the x- and y-coordinates are both different, the midpoint should be at the average values of the coordinates,

or at .   d. Form a right triangle with the segment formed by the two points as the hypotenuse. Note that the other coordinateis (x2, y1) in the drawing. 

 

We know the Pythagorean Theorem is a2 + b

2 = c

2. We can solve this formula for c by taking the square root of

each side. So, . Now we can replace the variables with the lengths of each side. The length of

side a is x2 – x1. The length of side b is y2 – y1. The length of side c is now .

 

46. ERROR ANALYSIS  Wyatt and Dario are determining whether 36, 77, and 85 form a Pythagorean triple. Is eitherof them correct? Explain your reasoning.

SOLUTION:  Wyatt is correct. The square of the greatest value should be equal to the sum of the squares of the two smaller values.  Since this is the case, the numbers form a Pythagorean triple.

47. CCSS PERSEVERANCE  Find the value of x in the figure shown.

SOLUTION:  The figure can be separated into two right triangles. Let m represent the missing side length common to both right

triangles. From the Pythagorean Theorem, m2 = 2

2 + x

2 and 14

2 = 8

2 + m

2. Using substitution, you can find that 2

2 +

x2 = 14

2 – 8

2.

Solve for x.

48. REASONING  Provide a counterexample to the statement. Any two right triangles with the same hypotenuse have the same area.

SOLUTION:  Different lengths of a and b can produce the same value of c in the Pythagorean theorem.  

 

Sample answer: A right triangle with legs measuring 3 cm and 4 cm has a hypotenuse of 5 cm and an area of 6 cm2.

A right triangle with legs measuring 2 cm and  cm also has a hypotenuse of 5 cm, but its area is   cm2,

which is not equivalent to 6 cm2.

49. OPEN ENDED  Draw a right triangle that has a hypotenuse of  units.

SOLUTION:  Use the Pythagorean Theorem to select two side lengths for a and b with the given value of c.

 

50. WRITING IN MATH  Explain how to determine whether segments in three lengths could form a right triangle.

SOLUTION:  

From the converse of the Pythagorean Theorem, if a2 + b

2 = c

2 then a, b, and c are the lengths of the side of a right

triangle. So, check to see whether the square of the greatest number is equal to the sum of the squares of the other two numbers. Consider triangle with sides of 9, 12 and 15 and a triangle with sides of 7, 13 and 19. 

   

51. GEOMETRY  Find the missing length.

A  −17

B  −

C  

D  17

SOLUTION:  

The correct choice is C.

52. What is a solution of this equation?

F  0, 3 G  3 H  0 J  no solutions

SOLUTION:  

The correct choice is H.

53. SHORT RESPONSE  A plumber charges $40 for the first hour of each house call plus $8 for each additional half hour. If the plumber works for 4 hours, how much does he charge?

SOLUTION:  Let x = the total number of hours worked.

The plumber charges $88 for 4 hours of work.

54. Find the next term in the geometric sequence .

A  

B  

C   

D  

SOLUTION:  

The correct choice is B.

Solve each equation. Check your solution.

55. 

SOLUTION:  

Check.

56. 

SOLUTION:  

Check.

57. 

SOLUTION:  

Check.

58. 

SOLUTION:  

Check.

59. 

SOLUTION:  

Check.

60. 

SOLUTION:  

Check.

There is no real solution.

Simplify each expression.

61. 

SOLUTION:  

62. 

SOLUTION:  

63. 

SOLUTION:  

64. 

SOLUTION:  

65. 

SOLUTION:  

66. 

SOLUTION:  

Describe how the graph of each function is related to the graph of f (x) = x2.

67. g(x) = x2 − 8

SOLUTION:  

The graph of f (x) = x2 + c represents a vertical translation of the parent graph. The value of c is –8, and –8 < 0. If c

< 0, the graph of f (x) = x2 is translated  units down. Therefore, the graph of g(x) = x

2 – 8 is a translation of the

parent graph shifted down 8 units.

68. h(x) = x2

SOLUTION:  

The graph of f (x) = ax2 stretches or compresses the graph of f (x) = x

2 vertically. The value of a is , and 0 <  <

1. If 0 <  < 1, the graph of f (x) = x2 is compressed vertically. Therefore, the graph of h(x) = x

2 is the parent

graph compressed vertically.

69. h(x) = −x2 + 5

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is 5, and 5 > 0. If c > 0, the graph of f (x) = x2 is translated

 units up. Therefore, the graph of h(x) = −x2 + 5 is a translation of the parent graph shifted up 8 units and

reflected across the x-axis.

70. g(x) = (x + 10)2

SOLUTION:  

The graph of f (x) = (x – c)2 represents a horizontal translation of the parent graph. The value of c is –10, and –10 <

0. If c < 0, the graph of f (x) = (x – c)2

is translated  units left. Therefore, the graph of g(x) = (x + 10)2 is a

translation of the parent graph shifted left 10 units.

71. g(x) = −2x2

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = ax

2 stretches or

compresses the graph of f (x) = x2 vertically. The value of a is –2, and |–2| > 1. If  > 1, the graph of f (x) = x

2 is

stretched vertically. Therefore, the graph of g(x) = –2x2 is the parent graph reflected across the x-axis and stretched

vertically.

72. h(x) = −x2 −

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is , and < 0. If c < 0, the graph of f (x) = x2 is

translated  units down. Therefore, the graph of h(x) = −x2 is a translation of the parent graph shifted down

 units and reflected across the x-axis.

73. ROCK CLIMBING  While rock climbing, Damaris launches a grappling hook from a height of 6 feet with an initialupward velocity of 56 feet per second. The hook just misses the stone ledge that she wants to scale. As it falls, the hook anchors on a ledge 30 feet above the ground. How long was the hook in the air?

SOLUTION:  

A half second after she throws the hook, it is 30 feet in the air. The hook continues up, then drops back down to the height of 30 feet 3 seconds after the throw. The hook was in the air for 3 seconds.

Find each product.74. (b + 8)(b + 2)

SOLUTION:  

75. (x − 4)(x − 9)

SOLUTION:  

76. (y + 4)(y − 8)

SOLUTION:  

77. (p + 2)(p − 10)

SOLUTION:  

78. (2w − 5)(w + 7)

SOLUTION:  

79. (8d + 3)(5d + 2)

SOLUTION:  

80. BUSINESS  The amount of money spent at West Outlet Mall continues to increase. The total T(x) in millions of

dollars can be estimated by the function T(x) = 12(1.12)x, where x is the number of years after it opened in 2005.

Find the amount of sales in 2015, 2016, and 2017.

SOLUTION:  

The sales for the mall in 2015 will be about $37.27 million; in 2016 will be about $41.74 million; and in 2017 will be about $46.75 million.

Solve each proportion.

81. 

SOLUTION:  

82. 

SOLUTION:  

83. 

SOLUTION:  

84. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 13

10-5 The Pythagorean Theorem

Page 14: Find each missing length. If necessary, round to the ......Find each missing length. If necessary, round to the nearest hundredth. 62/87,21 Use the Pythagorean Theorem, substituting

Find each missing length. If necessary, round to the nearest hundredth.

1. 

SOLUTION:  Use the Pythagorean Theorem, substituting 3 for a and 4 for b.

2. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 21 for c.

3. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for b and 19 for c.

4. 

SOLUTION:  Use the Pythagorean Theorem, substituting 8 for a and 12 for b.

5. BASEBALL  A baseball diamond is a square. The distance between consecutive bases is 90 feet.

a.  How far does a catcher have to throw the ball from home plate to second base? b.  How far does a third baseman throw the ball to the first baseman from a point in the baseline 15 feet from third to second base? c.  A base runner going from first to second base is 100 feet from home plate. How far is the runner from second base?

SOLUTION:  a. Use the Pythagorean Theorem, substituting 90 for a and 90 for b.

The catcher has to throw the ball about 127 ft from home plate to second base.   b. The diagram below illustrates the throw made by the third baseman.

The length of a is 90 – 15 or 75 feet. Find the length of the throw c by using the Pythagorean Theorem, substituting 75 for a and 90 for b.

The third baseman has to throw the ball about 117 feet to the first baseman.   c. The diagram below illustrates the position of the base runner.

Use the Pythagorean Theorem to find the length of side a by substituting 90 for b and 100 for c.

So, the base runner is about 44 feet from first base to second base. Therefore, the distance the base runner is from second is about 90 – 44 or 46 feet.  

Determine whether each set of measures can be the lengths of the sides of a right triangle.6. 8, 12, 16

SOLUTION:  

Since the measure of the longest side is 16, let c = 16, a = 8, and b = 12. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 8, 12, and 16 is not a right triangle.

7. 28, 45, 53

SOLUTION:  

Since the measure of the longest side is 53, let c = 53, a = 28, and b = 45. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 28, 45, and 53 is a right triangle.

8. 7, 24, 25

SOLUTION:  

Since the measure of the longest side is 25, let c = 25, a = 7, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 7, 24, and 25 is a right triangle.

9. 15, 25, 45

SOLUTION:  

Since the measure of the longest side is 45, let c = 45, a = 15, and b = 25. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 15, 25, and 45 is not a right triangle.

Find each missing length. If necessary, round to the nearest hundredth.

10. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for a and 14 for b.

11. 

SOLUTION:  Use the Pythagorean Theorem, substituting 2 for a and 12 for c.

12. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and 20 for b.

13. 

SOLUTION:  Use the Pythagorean Theorem, substituting 9 for b and 31 for c.

14. 

SOLUTION:  Use the Pythagorean Theorem, substituting 16 for a and 26 for c.

15. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and  for b.

16. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for b and 25 for c.

17. 

SOLUTION:  

Use the Pythagorean Theorem, substituting 5 for a and  for c.

18. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for b and  for c.

19. TELEVISION  Larry is buying an entertainment stand for his television. The diagonal of his television is 42 inches. The space for the television measures 30 inches by 36 inches. Will Larry’s television fit? Explain.

SOLUTION:  Use the Pythagorean Theorem, substituting 30 for a and 36 for b.

Yes; sample answer: The diagonal of the space in the TV stand is about 46.9 inches, which is greater than the diagonal of the television, so Larry’s TV will fit.

Determine whether each set of measures can be the lengths of the sides of a right triangle. Then determine whether they form a Pythagorean triple.

20. 9, 40, 41

SOLUTION:  

Since the measure of the longest side is 41, let c = 41, a = 9, and b = 40. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 9, 40, and 41 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

21. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = 3, and b = . Then determine whether c2 = a

2 +

b2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 3, , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

22. 

SOLUTION:  

Since the measure of the longest side is 12, let c = 12, a = 4, and b = . Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 4, , and 12 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

23. 

SOLUTION:  

Since the measure of the longest side is 14, let c = 14, a = , and b = 7. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths , 7, and 14 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

24. 8, 31.5, 32.5

SOLUTION:  

Since the measure of the longest side is 32.5, let c = 32.5, a = 8, and b = 31.5. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 8, 31.5, and 32.5 is a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number, but b and c are not whole numbers.

25. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = , and b = . Then determine whether c2 =

a2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths , , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

26. 18, 24, 30

SOLUTION:  

Since the measure of the longest side is 30, let c = 30, a = 18, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 18, 24, and 30 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

27. 36, 77, 85

SOLUTION:  

Since the measure of the longest side is 85, let c = 85, a = 36, and b = 77. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 36, 77, and 85 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

28. 17, 33, 98

SOLUTION:  Since the measure of the longest side is 98, let c = 98, a = 17, and b = 33. The length of c is greater than the sum of a and b, so this is not a triangle. 

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 17, 33, and 98 is not a triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

29. GEOMETRY  Refer to the triangle shown.

a.  What is a? b.  Find the area of the triangle.

SOLUTION:  a. Use the Pythagorean Theorem, substituting 11 for b and 23 for c.

b.

The area of the triangle is about 111.1 units2.

30. GARDENING  Khaliah wants to plant flowers in a triangular plot. She has three lengths of plastic garden edging that measure 8 feet, 15 feet, and 17 feet. Determine whether these pieces form a right triangle. Explain.

SOLUTION:  Yes; sample answer: The longest side is 17 feet so this has to be the hypotenuse.

82 + 15

2 = 17

2 so the pieces form a right triangle by the converse of the Pythagorean Theorem.

31. LADDER  Mr. Takeo is locked out of his house. The only open window is on the second floor. There is a bush along the edge of the house, so he places the neighbor’s ladder 10 feet from the house. To the nearest foot, what length of ladder does he need to reach the window?

SOLUTION:  Use the Pythagorean Theorem, substituting 10 for a and 28 for b.

He will need a 30-ft ladder to reach the window.

CCSS TOOLS  Find the length of the hypotenuse. Round to the nearest hundredth.

32. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for a and 10 for b.

33. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 7 for b.

34. DOLLHOUSE  Alonso is building a dollhouse for his sister’s birthday. The roof is 24 inches across and the slanted side is 16 inches long as shown. Find the height of the roof to the nearest tenth of an inch.

SOLUTION:  Use the Pythagorean Theorem, substituting 12 for b and 16 for c.

The height of the roof is 10.6 in.

35. GEOMETRY  Each side of a cube is 5 inches long. Find the length of a diagonal of the cube.

SOLUTION:  

Use the Pythagorean Theorem to find the diagonal of a side of the cube, substituting 5 for a and 5 for b.

Then, use the Pythagorean Theorem to find a diagonal of the cube, substituting 5 for a and  for b.

The length of a diagonal of the cube is about 8.66 in.

36. TOWN SQUARES  The largest town square in the world is Tiananmen Square in Beijing, China, covering 98 acres. a.  One square mile is 640 acres. Assuming that Tiananmen Square is a square, how many feet long is a side to the nearest foot? b.  To the nearest foot, what is the diagonal distance across Tiananmen Square?

SOLUTION:  a. First, use the conversion factor 1 square mile = 640 acres to convert the area of the square from acres to square miles.

So, 98 acres is 0.153125 square miles. Use dimensional analysis to convert this measure to square feet.  

  Next, use the formula for the area of a square to find the length of a side.

Therefore, a side of Tiananmen Square is about 2066 feet long.   b. Use the Pythagorean Theorem to find the length of the diagonal of the square, substituting 2066 for both a and b.

The diagonal distance across Tiananmen Square is about 2922 feet.

37. TRUCKS  Violeta needs to construct a ramp to roll a cart of moving boxes from her garage into the back of her truck. The truck is 6 feet from the garage. The back of the truck is 36 inches above the ground. How long does the ramp have to be?

SOLUTION:  First, rewrite 36 inches as 3 ft. Use the Pythagorean thereom, substituting 6 for a and 3 for b.

The ramp must be about 6.7 ft.

If c is the measure of the hypotenuse of a right triangle, find each missing measure. If necessary, round to the nearest hundredth.

38. a = x, b = x + 41, c = 85

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 36; b = 77

39. a = 8, b = x, c = x + 2

SOLUTION:  

b = 15; c = 17

40. a = 12, b = x − 2, c = x

SOLUTION:  

b = 35; c = 37

41. a = x, b = x + 7, c = 97

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 65; b = 72

42. a = x − 47, b = x, c = x + 2

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 16; b = 63; c = 65

43. a = x − 32, b = x − 1, c = x

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 9; b = 40; c = 41

44. GEOMETRY  A right triangle has one leg that is 8 inches shorter than the other leg. The hypotenuse is 30 inches long. Find the length of each leg.

SOLUTION:  

The length of each leg of the triangle is about 24.83 in. and about 16.83 in.

45. MULTIPLE REPRESENTATIONS In this problem, you will derive a method for finding the midpoint and length of a segment on the coordinate plane. a. Graphical Use a graph to find the lengths of the segments between (3, 2) and (8, 2) and between (4, 1) and (4, 9).Then find the midpoint of each segment. b. Logical Use what you learned in part a to write expressions for the lengths of the segments between (x1 , y) and

(x2 , y) and between (x, y1 ) and (x,  y2). What would be the midpoint of each segment?

c. Analytical Based on your results from part b, find the midpoint of the segment with endpoints at (x1, y1), and (x2,

y2).

d. Analytical Use the Pythagorean Theorem to write an expression for the distance between (x1, y1), and (x2, y2).

SOLUTION:  a.  From the graph, the length of the vertical segment is 9 – 1 or 8 units and the length of the horizontal line is 8 – 3 or 5 units.

The midpoints will be located in the middle of each segment, or the average of the coordinates. For the vertical segment, the value between 1 and 9 is 5, so the midpoint should be at (4, 5). For the horizontal segment, the value between 3 and 8 is 5.5, so the midpoint should be at (5.5, 2). b.  Distance: The length of the segment between (x1, y) and (x2, y) will be the absolute value of x1 – x2. The length

of the segment between (x, y1) and (x, y2) will be the absolute value of y1 – y2.

Midpoint: When the x-coordinates are identical, then the x-coordinate of the midpoint will also be the same value.

This is true for the y-coordinates as well. The midpoint of (x1, y) and (x2, y) is at the average of the x-coordinates

and y or at , and the midpoint of (x, y1) and (x, y2) is at .

c. When the x- and y-coordinates are both different, the midpoint should be at the average values of the coordinates,

or at .   d. Form a right triangle with the segment formed by the two points as the hypotenuse. Note that the other coordinateis (x2, y1) in the drawing. 

 

We know the Pythagorean Theorem is a2 + b

2 = c

2. We can solve this formula for c by taking the square root of

each side. So, . Now we can replace the variables with the lengths of each side. The length of

side a is x2 – x1. The length of side b is y2 – y1. The length of side c is now .

 

46. ERROR ANALYSIS  Wyatt and Dario are determining whether 36, 77, and 85 form a Pythagorean triple. Is eitherof them correct? Explain your reasoning.

SOLUTION:  Wyatt is correct. The square of the greatest value should be equal to the sum of the squares of the two smaller values.  Since this is the case, the numbers form a Pythagorean triple.

47. CCSS PERSEVERANCE  Find the value of x in the figure shown.

SOLUTION:  The figure can be separated into two right triangles. Let m represent the missing side length common to both right

triangles. From the Pythagorean Theorem, m2 = 2

2 + x

2 and 14

2 = 8

2 + m

2. Using substitution, you can find that 2

2 +

x2 = 14

2 – 8

2.

Solve for x.

48. REASONING  Provide a counterexample to the statement. Any two right triangles with the same hypotenuse have the same area.

SOLUTION:  Different lengths of a and b can produce the same value of c in the Pythagorean theorem.  

 

Sample answer: A right triangle with legs measuring 3 cm and 4 cm has a hypotenuse of 5 cm and an area of 6 cm2.

A right triangle with legs measuring 2 cm and  cm also has a hypotenuse of 5 cm, but its area is   cm2,

which is not equivalent to 6 cm2.

49. OPEN ENDED  Draw a right triangle that has a hypotenuse of  units.

SOLUTION:  Use the Pythagorean Theorem to select two side lengths for a and b with the given value of c.

 

50. WRITING IN MATH  Explain how to determine whether segments in three lengths could form a right triangle.

SOLUTION:  

From the converse of the Pythagorean Theorem, if a2 + b

2 = c

2 then a, b, and c are the lengths of the side of a right

triangle. So, check to see whether the square of the greatest number is equal to the sum of the squares of the other two numbers. Consider triangle with sides of 9, 12 and 15 and a triangle with sides of 7, 13 and 19. 

   

51. GEOMETRY  Find the missing length.

A  −17

B  −

C  

D  17

SOLUTION:  

The correct choice is C.

52. What is a solution of this equation?

F  0, 3 G  3 H  0 J  no solutions

SOLUTION:  

The correct choice is H.

53. SHORT RESPONSE  A plumber charges $40 for the first hour of each house call plus $8 for each additional half hour. If the plumber works for 4 hours, how much does he charge?

SOLUTION:  Let x = the total number of hours worked.

The plumber charges $88 for 4 hours of work.

54. Find the next term in the geometric sequence .

A  

B  

C   

D  

SOLUTION:  

The correct choice is B.

Solve each equation. Check your solution.

55. 

SOLUTION:  

Check.

56. 

SOLUTION:  

Check.

57. 

SOLUTION:  

Check.

58. 

SOLUTION:  

Check.

59. 

SOLUTION:  

Check.

60. 

SOLUTION:  

Check.

There is no real solution.

Simplify each expression.

61. 

SOLUTION:  

62. 

SOLUTION:  

63. 

SOLUTION:  

64. 

SOLUTION:  

65. 

SOLUTION:  

66. 

SOLUTION:  

Describe how the graph of each function is related to the graph of f (x) = x2.

67. g(x) = x2 − 8

SOLUTION:  

The graph of f (x) = x2 + c represents a vertical translation of the parent graph. The value of c is –8, and –8 < 0. If c

< 0, the graph of f (x) = x2 is translated  units down. Therefore, the graph of g(x) = x

2 – 8 is a translation of the

parent graph shifted down 8 units.

68. h(x) = x2

SOLUTION:  

The graph of f (x) = ax2 stretches or compresses the graph of f (x) = x

2 vertically. The value of a is , and 0 <  <

1. If 0 <  < 1, the graph of f (x) = x2 is compressed vertically. Therefore, the graph of h(x) = x

2 is the parent

graph compressed vertically.

69. h(x) = −x2 + 5

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is 5, and 5 > 0. If c > 0, the graph of f (x) = x2 is translated

 units up. Therefore, the graph of h(x) = −x2 + 5 is a translation of the parent graph shifted up 8 units and

reflected across the x-axis.

70. g(x) = (x + 10)2

SOLUTION:  

The graph of f (x) = (x – c)2 represents a horizontal translation of the parent graph. The value of c is –10, and –10 <

0. If c < 0, the graph of f (x) = (x – c)2

is translated  units left. Therefore, the graph of g(x) = (x + 10)2 is a

translation of the parent graph shifted left 10 units.

71. g(x) = −2x2

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = ax

2 stretches or

compresses the graph of f (x) = x2 vertically. The value of a is –2, and |–2| > 1. If  > 1, the graph of f (x) = x

2 is

stretched vertically. Therefore, the graph of g(x) = –2x2 is the parent graph reflected across the x-axis and stretched

vertically.

72. h(x) = −x2 −

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is , and < 0. If c < 0, the graph of f (x) = x2 is

translated  units down. Therefore, the graph of h(x) = −x2 is a translation of the parent graph shifted down

 units and reflected across the x-axis.

73. ROCK CLIMBING  While rock climbing, Damaris launches a grappling hook from a height of 6 feet with an initialupward velocity of 56 feet per second. The hook just misses the stone ledge that she wants to scale. As it falls, the hook anchors on a ledge 30 feet above the ground. How long was the hook in the air?

SOLUTION:  

A half second after she throws the hook, it is 30 feet in the air. The hook continues up, then drops back down to the height of 30 feet 3 seconds after the throw. The hook was in the air for 3 seconds.

Find each product.74. (b + 8)(b + 2)

SOLUTION:  

75. (x − 4)(x − 9)

SOLUTION:  

76. (y + 4)(y − 8)

SOLUTION:  

77. (p + 2)(p − 10)

SOLUTION:  

78. (2w − 5)(w + 7)

SOLUTION:  

79. (8d + 3)(5d + 2)

SOLUTION:  

80. BUSINESS  The amount of money spent at West Outlet Mall continues to increase. The total T(x) in millions of

dollars can be estimated by the function T(x) = 12(1.12)x, where x is the number of years after it opened in 2005.

Find the amount of sales in 2015, 2016, and 2017.

SOLUTION:  

The sales for the mall in 2015 will be about $37.27 million; in 2016 will be about $41.74 million; and in 2017 will be about $46.75 million.

Solve each proportion.

81. 

SOLUTION:  

82. 

SOLUTION:  

83. 

SOLUTION:  

84. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 14

10-5 The Pythagorean Theorem

Page 15: Find each missing length. If necessary, round to the ......Find each missing length. If necessary, round to the nearest hundredth. 62/87,21 Use the Pythagorean Theorem, substituting

Find each missing length. If necessary, round to the nearest hundredth.

1. 

SOLUTION:  Use the Pythagorean Theorem, substituting 3 for a and 4 for b.

2. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 21 for c.

3. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for b and 19 for c.

4. 

SOLUTION:  Use the Pythagorean Theorem, substituting 8 for a and 12 for b.

5. BASEBALL  A baseball diamond is a square. The distance between consecutive bases is 90 feet.

a.  How far does a catcher have to throw the ball from home plate to second base? b.  How far does a third baseman throw the ball to the first baseman from a point in the baseline 15 feet from third to second base? c.  A base runner going from first to second base is 100 feet from home plate. How far is the runner from second base?

SOLUTION:  a. Use the Pythagorean Theorem, substituting 90 for a and 90 for b.

The catcher has to throw the ball about 127 ft from home plate to second base.   b. The diagram below illustrates the throw made by the third baseman.

The length of a is 90 – 15 or 75 feet. Find the length of the throw c by using the Pythagorean Theorem, substituting 75 for a and 90 for b.

The third baseman has to throw the ball about 117 feet to the first baseman.   c. The diagram below illustrates the position of the base runner.

Use the Pythagorean Theorem to find the length of side a by substituting 90 for b and 100 for c.

So, the base runner is about 44 feet from first base to second base. Therefore, the distance the base runner is from second is about 90 – 44 or 46 feet.  

Determine whether each set of measures can be the lengths of the sides of a right triangle.6. 8, 12, 16

SOLUTION:  

Since the measure of the longest side is 16, let c = 16, a = 8, and b = 12. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 8, 12, and 16 is not a right triangle.

7. 28, 45, 53

SOLUTION:  

Since the measure of the longest side is 53, let c = 53, a = 28, and b = 45. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 28, 45, and 53 is a right triangle.

8. 7, 24, 25

SOLUTION:  

Since the measure of the longest side is 25, let c = 25, a = 7, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 7, 24, and 25 is a right triangle.

9. 15, 25, 45

SOLUTION:  

Since the measure of the longest side is 45, let c = 45, a = 15, and b = 25. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 15, 25, and 45 is not a right triangle.

Find each missing length. If necessary, round to the nearest hundredth.

10. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for a and 14 for b.

11. 

SOLUTION:  Use the Pythagorean Theorem, substituting 2 for a and 12 for c.

12. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and 20 for b.

13. 

SOLUTION:  Use the Pythagorean Theorem, substituting 9 for b and 31 for c.

14. 

SOLUTION:  Use the Pythagorean Theorem, substituting 16 for a and 26 for c.

15. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and  for b.

16. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for b and 25 for c.

17. 

SOLUTION:  

Use the Pythagorean Theorem, substituting 5 for a and  for c.

18. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for b and  for c.

19. TELEVISION  Larry is buying an entertainment stand for his television. The diagonal of his television is 42 inches. The space for the television measures 30 inches by 36 inches. Will Larry’s television fit? Explain.

SOLUTION:  Use the Pythagorean Theorem, substituting 30 for a and 36 for b.

Yes; sample answer: The diagonal of the space in the TV stand is about 46.9 inches, which is greater than the diagonal of the television, so Larry’s TV will fit.

Determine whether each set of measures can be the lengths of the sides of a right triangle. Then determine whether they form a Pythagorean triple.

20. 9, 40, 41

SOLUTION:  

Since the measure of the longest side is 41, let c = 41, a = 9, and b = 40. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 9, 40, and 41 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

21. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = 3, and b = . Then determine whether c2 = a

2 +

b2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 3, , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

22. 

SOLUTION:  

Since the measure of the longest side is 12, let c = 12, a = 4, and b = . Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 4, , and 12 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

23. 

SOLUTION:  

Since the measure of the longest side is 14, let c = 14, a = , and b = 7. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths , 7, and 14 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

24. 8, 31.5, 32.5

SOLUTION:  

Since the measure of the longest side is 32.5, let c = 32.5, a = 8, and b = 31.5. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 8, 31.5, and 32.5 is a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number, but b and c are not whole numbers.

25. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = , and b = . Then determine whether c2 =

a2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths , , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

26. 18, 24, 30

SOLUTION:  

Since the measure of the longest side is 30, let c = 30, a = 18, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 18, 24, and 30 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

27. 36, 77, 85

SOLUTION:  

Since the measure of the longest side is 85, let c = 85, a = 36, and b = 77. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 36, 77, and 85 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

28. 17, 33, 98

SOLUTION:  Since the measure of the longest side is 98, let c = 98, a = 17, and b = 33. The length of c is greater than the sum of a and b, so this is not a triangle. 

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 17, 33, and 98 is not a triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

29. GEOMETRY  Refer to the triangle shown.

a.  What is a? b.  Find the area of the triangle.

SOLUTION:  a. Use the Pythagorean Theorem, substituting 11 for b and 23 for c.

b.

The area of the triangle is about 111.1 units2.

30. GARDENING  Khaliah wants to plant flowers in a triangular plot. She has three lengths of plastic garden edging that measure 8 feet, 15 feet, and 17 feet. Determine whether these pieces form a right triangle. Explain.

SOLUTION:  Yes; sample answer: The longest side is 17 feet so this has to be the hypotenuse.

82 + 15

2 = 17

2 so the pieces form a right triangle by the converse of the Pythagorean Theorem.

31. LADDER  Mr. Takeo is locked out of his house. The only open window is on the second floor. There is a bush along the edge of the house, so he places the neighbor’s ladder 10 feet from the house. To the nearest foot, what length of ladder does he need to reach the window?

SOLUTION:  Use the Pythagorean Theorem, substituting 10 for a and 28 for b.

He will need a 30-ft ladder to reach the window.

CCSS TOOLS  Find the length of the hypotenuse. Round to the nearest hundredth.

32. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for a and 10 for b.

33. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 7 for b.

34. DOLLHOUSE  Alonso is building a dollhouse for his sister’s birthday. The roof is 24 inches across and the slanted side is 16 inches long as shown. Find the height of the roof to the nearest tenth of an inch.

SOLUTION:  Use the Pythagorean Theorem, substituting 12 for b and 16 for c.

The height of the roof is 10.6 in.

35. GEOMETRY  Each side of a cube is 5 inches long. Find the length of a diagonal of the cube.

SOLUTION:  

Use the Pythagorean Theorem to find the diagonal of a side of the cube, substituting 5 for a and 5 for b.

Then, use the Pythagorean Theorem to find a diagonal of the cube, substituting 5 for a and  for b.

The length of a diagonal of the cube is about 8.66 in.

36. TOWN SQUARES  The largest town square in the world is Tiananmen Square in Beijing, China, covering 98 acres. a.  One square mile is 640 acres. Assuming that Tiananmen Square is a square, how many feet long is a side to the nearest foot? b.  To the nearest foot, what is the diagonal distance across Tiananmen Square?

SOLUTION:  a. First, use the conversion factor 1 square mile = 640 acres to convert the area of the square from acres to square miles.

So, 98 acres is 0.153125 square miles. Use dimensional analysis to convert this measure to square feet.  

  Next, use the formula for the area of a square to find the length of a side.

Therefore, a side of Tiananmen Square is about 2066 feet long.   b. Use the Pythagorean Theorem to find the length of the diagonal of the square, substituting 2066 for both a and b.

The diagonal distance across Tiananmen Square is about 2922 feet.

37. TRUCKS  Violeta needs to construct a ramp to roll a cart of moving boxes from her garage into the back of her truck. The truck is 6 feet from the garage. The back of the truck is 36 inches above the ground. How long does the ramp have to be?

SOLUTION:  First, rewrite 36 inches as 3 ft. Use the Pythagorean thereom, substituting 6 for a and 3 for b.

The ramp must be about 6.7 ft.

If c is the measure of the hypotenuse of a right triangle, find each missing measure. If necessary, round to the nearest hundredth.

38. a = x, b = x + 41, c = 85

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 36; b = 77

39. a = 8, b = x, c = x + 2

SOLUTION:  

b = 15; c = 17

40. a = 12, b = x − 2, c = x

SOLUTION:  

b = 35; c = 37

41. a = x, b = x + 7, c = 97

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 65; b = 72

42. a = x − 47, b = x, c = x + 2

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 16; b = 63; c = 65

43. a = x − 32, b = x − 1, c = x

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 9; b = 40; c = 41

44. GEOMETRY  A right triangle has one leg that is 8 inches shorter than the other leg. The hypotenuse is 30 inches long. Find the length of each leg.

SOLUTION:  

The length of each leg of the triangle is about 24.83 in. and about 16.83 in.

45. MULTIPLE REPRESENTATIONS In this problem, you will derive a method for finding the midpoint and length of a segment on the coordinate plane. a. Graphical Use a graph to find the lengths of the segments between (3, 2) and (8, 2) and between (4, 1) and (4, 9).Then find the midpoint of each segment. b. Logical Use what you learned in part a to write expressions for the lengths of the segments between (x1 , y) and

(x2 , y) and between (x, y1 ) and (x,  y2). What would be the midpoint of each segment?

c. Analytical Based on your results from part b, find the midpoint of the segment with endpoints at (x1, y1), and (x2,

y2).

d. Analytical Use the Pythagorean Theorem to write an expression for the distance between (x1, y1), and (x2, y2).

SOLUTION:  a.  From the graph, the length of the vertical segment is 9 – 1 or 8 units and the length of the horizontal line is 8 – 3 or 5 units.

The midpoints will be located in the middle of each segment, or the average of the coordinates. For the vertical segment, the value between 1 and 9 is 5, so the midpoint should be at (4, 5). For the horizontal segment, the value between 3 and 8 is 5.5, so the midpoint should be at (5.5, 2). b.  Distance: The length of the segment between (x1, y) and (x2, y) will be the absolute value of x1 – x2. The length

of the segment between (x, y1) and (x, y2) will be the absolute value of y1 – y2.

Midpoint: When the x-coordinates are identical, then the x-coordinate of the midpoint will also be the same value.

This is true for the y-coordinates as well. The midpoint of (x1, y) and (x2, y) is at the average of the x-coordinates

and y or at , and the midpoint of (x, y1) and (x, y2) is at .

c. When the x- and y-coordinates are both different, the midpoint should be at the average values of the coordinates,

or at .   d. Form a right triangle with the segment formed by the two points as the hypotenuse. Note that the other coordinateis (x2, y1) in the drawing. 

 

We know the Pythagorean Theorem is a2 + b

2 = c

2. We can solve this formula for c by taking the square root of

each side. So, . Now we can replace the variables with the lengths of each side. The length of

side a is x2 – x1. The length of side b is y2 – y1. The length of side c is now .

 

46. ERROR ANALYSIS  Wyatt and Dario are determining whether 36, 77, and 85 form a Pythagorean triple. Is eitherof them correct? Explain your reasoning.

SOLUTION:  Wyatt is correct. The square of the greatest value should be equal to the sum of the squares of the two smaller values.  Since this is the case, the numbers form a Pythagorean triple.

47. CCSS PERSEVERANCE  Find the value of x in the figure shown.

SOLUTION:  The figure can be separated into two right triangles. Let m represent the missing side length common to both right

triangles. From the Pythagorean Theorem, m2 = 2

2 + x

2 and 14

2 = 8

2 + m

2. Using substitution, you can find that 2

2 +

x2 = 14

2 – 8

2.

Solve for x.

48. REASONING  Provide a counterexample to the statement. Any two right triangles with the same hypotenuse have the same area.

SOLUTION:  Different lengths of a and b can produce the same value of c in the Pythagorean theorem.  

 

Sample answer: A right triangle with legs measuring 3 cm and 4 cm has a hypotenuse of 5 cm and an area of 6 cm2.

A right triangle with legs measuring 2 cm and  cm also has a hypotenuse of 5 cm, but its area is   cm2,

which is not equivalent to 6 cm2.

49. OPEN ENDED  Draw a right triangle that has a hypotenuse of  units.

SOLUTION:  Use the Pythagorean Theorem to select two side lengths for a and b with the given value of c.

 

50. WRITING IN MATH  Explain how to determine whether segments in three lengths could form a right triangle.

SOLUTION:  

From the converse of the Pythagorean Theorem, if a2 + b

2 = c

2 then a, b, and c are the lengths of the side of a right

triangle. So, check to see whether the square of the greatest number is equal to the sum of the squares of the other two numbers. Consider triangle with sides of 9, 12 and 15 and a triangle with sides of 7, 13 and 19. 

   

51. GEOMETRY  Find the missing length.

A  −17

B  −

C  

D  17

SOLUTION:  

The correct choice is C.

52. What is a solution of this equation?

F  0, 3 G  3 H  0 J  no solutions

SOLUTION:  

The correct choice is H.

53. SHORT RESPONSE  A plumber charges $40 for the first hour of each house call plus $8 for each additional half hour. If the plumber works for 4 hours, how much does he charge?

SOLUTION:  Let x = the total number of hours worked.

The plumber charges $88 for 4 hours of work.

54. Find the next term in the geometric sequence .

A  

B  

C   

D  

SOLUTION:  

The correct choice is B.

Solve each equation. Check your solution.

55. 

SOLUTION:  

Check.

56. 

SOLUTION:  

Check.

57. 

SOLUTION:  

Check.

58. 

SOLUTION:  

Check.

59. 

SOLUTION:  

Check.

60. 

SOLUTION:  

Check.

There is no real solution.

Simplify each expression.

61. 

SOLUTION:  

62. 

SOLUTION:  

63. 

SOLUTION:  

64. 

SOLUTION:  

65. 

SOLUTION:  

66. 

SOLUTION:  

Describe how the graph of each function is related to the graph of f (x) = x2.

67. g(x) = x2 − 8

SOLUTION:  

The graph of f (x) = x2 + c represents a vertical translation of the parent graph. The value of c is –8, and –8 < 0. If c

< 0, the graph of f (x) = x2 is translated  units down. Therefore, the graph of g(x) = x

2 – 8 is a translation of the

parent graph shifted down 8 units.

68. h(x) = x2

SOLUTION:  

The graph of f (x) = ax2 stretches or compresses the graph of f (x) = x

2 vertically. The value of a is , and 0 <  <

1. If 0 <  < 1, the graph of f (x) = x2 is compressed vertically. Therefore, the graph of h(x) = x

2 is the parent

graph compressed vertically.

69. h(x) = −x2 + 5

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is 5, and 5 > 0. If c > 0, the graph of f (x) = x2 is translated

 units up. Therefore, the graph of h(x) = −x2 + 5 is a translation of the parent graph shifted up 8 units and

reflected across the x-axis.

70. g(x) = (x + 10)2

SOLUTION:  

The graph of f (x) = (x – c)2 represents a horizontal translation of the parent graph. The value of c is –10, and –10 <

0. If c < 0, the graph of f (x) = (x – c)2

is translated  units left. Therefore, the graph of g(x) = (x + 10)2 is a

translation of the parent graph shifted left 10 units.

71. g(x) = −2x2

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = ax

2 stretches or

compresses the graph of f (x) = x2 vertically. The value of a is –2, and |–2| > 1. If  > 1, the graph of f (x) = x

2 is

stretched vertically. Therefore, the graph of g(x) = –2x2 is the parent graph reflected across the x-axis and stretched

vertically.

72. h(x) = −x2 −

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is , and < 0. If c < 0, the graph of f (x) = x2 is

translated  units down. Therefore, the graph of h(x) = −x2 is a translation of the parent graph shifted down

 units and reflected across the x-axis.

73. ROCK CLIMBING  While rock climbing, Damaris launches a grappling hook from a height of 6 feet with an initialupward velocity of 56 feet per second. The hook just misses the stone ledge that she wants to scale. As it falls, the hook anchors on a ledge 30 feet above the ground. How long was the hook in the air?

SOLUTION:  

A half second after she throws the hook, it is 30 feet in the air. The hook continues up, then drops back down to the height of 30 feet 3 seconds after the throw. The hook was in the air for 3 seconds.

Find each product.74. (b + 8)(b + 2)

SOLUTION:  

75. (x − 4)(x − 9)

SOLUTION:  

76. (y + 4)(y − 8)

SOLUTION:  

77. (p + 2)(p − 10)

SOLUTION:  

78. (2w − 5)(w + 7)

SOLUTION:  

79. (8d + 3)(5d + 2)

SOLUTION:  

80. BUSINESS  The amount of money spent at West Outlet Mall continues to increase. The total T(x) in millions of

dollars can be estimated by the function T(x) = 12(1.12)x, where x is the number of years after it opened in 2005.

Find the amount of sales in 2015, 2016, and 2017.

SOLUTION:  

The sales for the mall in 2015 will be about $37.27 million; in 2016 will be about $41.74 million; and in 2017 will be about $46.75 million.

Solve each proportion.

81. 

SOLUTION:  

82. 

SOLUTION:  

83. 

SOLUTION:  

84. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 15

10-5 The Pythagorean Theorem

Page 16: Find each missing length. If necessary, round to the ......Find each missing length. If necessary, round to the nearest hundredth. 62/87,21 Use the Pythagorean Theorem, substituting

Find each missing length. If necessary, round to the nearest hundredth.

1. 

SOLUTION:  Use the Pythagorean Theorem, substituting 3 for a and 4 for b.

2. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 21 for c.

3. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for b and 19 for c.

4. 

SOLUTION:  Use the Pythagorean Theorem, substituting 8 for a and 12 for b.

5. BASEBALL  A baseball diamond is a square. The distance between consecutive bases is 90 feet.

a.  How far does a catcher have to throw the ball from home plate to second base? b.  How far does a third baseman throw the ball to the first baseman from a point in the baseline 15 feet from third to second base? c.  A base runner going from first to second base is 100 feet from home plate. How far is the runner from second base?

SOLUTION:  a. Use the Pythagorean Theorem, substituting 90 for a and 90 for b.

The catcher has to throw the ball about 127 ft from home plate to second base.   b. The diagram below illustrates the throw made by the third baseman.

The length of a is 90 – 15 or 75 feet. Find the length of the throw c by using the Pythagorean Theorem, substituting 75 for a and 90 for b.

The third baseman has to throw the ball about 117 feet to the first baseman.   c. The diagram below illustrates the position of the base runner.

Use the Pythagorean Theorem to find the length of side a by substituting 90 for b and 100 for c.

So, the base runner is about 44 feet from first base to second base. Therefore, the distance the base runner is from second is about 90 – 44 or 46 feet.  

Determine whether each set of measures can be the lengths of the sides of a right triangle.6. 8, 12, 16

SOLUTION:  

Since the measure of the longest side is 16, let c = 16, a = 8, and b = 12. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 8, 12, and 16 is not a right triangle.

7. 28, 45, 53

SOLUTION:  

Since the measure of the longest side is 53, let c = 53, a = 28, and b = 45. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 28, 45, and 53 is a right triangle.

8. 7, 24, 25

SOLUTION:  

Since the measure of the longest side is 25, let c = 25, a = 7, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 7, 24, and 25 is a right triangle.

9. 15, 25, 45

SOLUTION:  

Since the measure of the longest side is 45, let c = 45, a = 15, and b = 25. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 15, 25, and 45 is not a right triangle.

Find each missing length. If necessary, round to the nearest hundredth.

10. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for a and 14 for b.

11. 

SOLUTION:  Use the Pythagorean Theorem, substituting 2 for a and 12 for c.

12. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and 20 for b.

13. 

SOLUTION:  Use the Pythagorean Theorem, substituting 9 for b and 31 for c.

14. 

SOLUTION:  Use the Pythagorean Theorem, substituting 16 for a and 26 for c.

15. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and  for b.

16. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for b and 25 for c.

17. 

SOLUTION:  

Use the Pythagorean Theorem, substituting 5 for a and  for c.

18. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for b and  for c.

19. TELEVISION  Larry is buying an entertainment stand for his television. The diagonal of his television is 42 inches. The space for the television measures 30 inches by 36 inches. Will Larry’s television fit? Explain.

SOLUTION:  Use the Pythagorean Theorem, substituting 30 for a and 36 for b.

Yes; sample answer: The diagonal of the space in the TV stand is about 46.9 inches, which is greater than the diagonal of the television, so Larry’s TV will fit.

Determine whether each set of measures can be the lengths of the sides of a right triangle. Then determine whether they form a Pythagorean triple.

20. 9, 40, 41

SOLUTION:  

Since the measure of the longest side is 41, let c = 41, a = 9, and b = 40. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 9, 40, and 41 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

21. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = 3, and b = . Then determine whether c2 = a

2 +

b2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 3, , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

22. 

SOLUTION:  

Since the measure of the longest side is 12, let c = 12, a = 4, and b = . Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 4, , and 12 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

23. 

SOLUTION:  

Since the measure of the longest side is 14, let c = 14, a = , and b = 7. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths , 7, and 14 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

24. 8, 31.5, 32.5

SOLUTION:  

Since the measure of the longest side is 32.5, let c = 32.5, a = 8, and b = 31.5. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 8, 31.5, and 32.5 is a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number, but b and c are not whole numbers.

25. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = , and b = . Then determine whether c2 =

a2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths , , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

26. 18, 24, 30

SOLUTION:  

Since the measure of the longest side is 30, let c = 30, a = 18, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 18, 24, and 30 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

27. 36, 77, 85

SOLUTION:  

Since the measure of the longest side is 85, let c = 85, a = 36, and b = 77. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 36, 77, and 85 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

28. 17, 33, 98

SOLUTION:  Since the measure of the longest side is 98, let c = 98, a = 17, and b = 33. The length of c is greater than the sum of a and b, so this is not a triangle. 

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 17, 33, and 98 is not a triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

29. GEOMETRY  Refer to the triangle shown.

a.  What is a? b.  Find the area of the triangle.

SOLUTION:  a. Use the Pythagorean Theorem, substituting 11 for b and 23 for c.

b.

The area of the triangle is about 111.1 units2.

30. GARDENING  Khaliah wants to plant flowers in a triangular plot. She has three lengths of plastic garden edging that measure 8 feet, 15 feet, and 17 feet. Determine whether these pieces form a right triangle. Explain.

SOLUTION:  Yes; sample answer: The longest side is 17 feet so this has to be the hypotenuse.

82 + 15

2 = 17

2 so the pieces form a right triangle by the converse of the Pythagorean Theorem.

31. LADDER  Mr. Takeo is locked out of his house. The only open window is on the second floor. There is a bush along the edge of the house, so he places the neighbor’s ladder 10 feet from the house. To the nearest foot, what length of ladder does he need to reach the window?

SOLUTION:  Use the Pythagorean Theorem, substituting 10 for a and 28 for b.

He will need a 30-ft ladder to reach the window.

CCSS TOOLS  Find the length of the hypotenuse. Round to the nearest hundredth.

32. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for a and 10 for b.

33. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 7 for b.

34. DOLLHOUSE  Alonso is building a dollhouse for his sister’s birthday. The roof is 24 inches across and the slanted side is 16 inches long as shown. Find the height of the roof to the nearest tenth of an inch.

SOLUTION:  Use the Pythagorean Theorem, substituting 12 for b and 16 for c.

The height of the roof is 10.6 in.

35. GEOMETRY  Each side of a cube is 5 inches long. Find the length of a diagonal of the cube.

SOLUTION:  

Use the Pythagorean Theorem to find the diagonal of a side of the cube, substituting 5 for a and 5 for b.

Then, use the Pythagorean Theorem to find a diagonal of the cube, substituting 5 for a and  for b.

The length of a diagonal of the cube is about 8.66 in.

36. TOWN SQUARES  The largest town square in the world is Tiananmen Square in Beijing, China, covering 98 acres. a.  One square mile is 640 acres. Assuming that Tiananmen Square is a square, how many feet long is a side to the nearest foot? b.  To the nearest foot, what is the diagonal distance across Tiananmen Square?

SOLUTION:  a. First, use the conversion factor 1 square mile = 640 acres to convert the area of the square from acres to square miles.

So, 98 acres is 0.153125 square miles. Use dimensional analysis to convert this measure to square feet.  

  Next, use the formula for the area of a square to find the length of a side.

Therefore, a side of Tiananmen Square is about 2066 feet long.   b. Use the Pythagorean Theorem to find the length of the diagonal of the square, substituting 2066 for both a and b.

The diagonal distance across Tiananmen Square is about 2922 feet.

37. TRUCKS  Violeta needs to construct a ramp to roll a cart of moving boxes from her garage into the back of her truck. The truck is 6 feet from the garage. The back of the truck is 36 inches above the ground. How long does the ramp have to be?

SOLUTION:  First, rewrite 36 inches as 3 ft. Use the Pythagorean thereom, substituting 6 for a and 3 for b.

The ramp must be about 6.7 ft.

If c is the measure of the hypotenuse of a right triangle, find each missing measure. If necessary, round to the nearest hundredth.

38. a = x, b = x + 41, c = 85

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 36; b = 77

39. a = 8, b = x, c = x + 2

SOLUTION:  

b = 15; c = 17

40. a = 12, b = x − 2, c = x

SOLUTION:  

b = 35; c = 37

41. a = x, b = x + 7, c = 97

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 65; b = 72

42. a = x − 47, b = x, c = x + 2

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 16; b = 63; c = 65

43. a = x − 32, b = x − 1, c = x

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 9; b = 40; c = 41

44. GEOMETRY  A right triangle has one leg that is 8 inches shorter than the other leg. The hypotenuse is 30 inches long. Find the length of each leg.

SOLUTION:  

The length of each leg of the triangle is about 24.83 in. and about 16.83 in.

45. MULTIPLE REPRESENTATIONS In this problem, you will derive a method for finding the midpoint and length of a segment on the coordinate plane. a. Graphical Use a graph to find the lengths of the segments between (3, 2) and (8, 2) and between (4, 1) and (4, 9).Then find the midpoint of each segment. b. Logical Use what you learned in part a to write expressions for the lengths of the segments between (x1 , y) and

(x2 , y) and between (x, y1 ) and (x,  y2). What would be the midpoint of each segment?

c. Analytical Based on your results from part b, find the midpoint of the segment with endpoints at (x1, y1), and (x2,

y2).

d. Analytical Use the Pythagorean Theorem to write an expression for the distance between (x1, y1), and (x2, y2).

SOLUTION:  a.  From the graph, the length of the vertical segment is 9 – 1 or 8 units and the length of the horizontal line is 8 – 3 or 5 units.

The midpoints will be located in the middle of each segment, or the average of the coordinates. For the vertical segment, the value between 1 and 9 is 5, so the midpoint should be at (4, 5). For the horizontal segment, the value between 3 and 8 is 5.5, so the midpoint should be at (5.5, 2). b.  Distance: The length of the segment between (x1, y) and (x2, y) will be the absolute value of x1 – x2. The length

of the segment between (x, y1) and (x, y2) will be the absolute value of y1 – y2.

Midpoint: When the x-coordinates are identical, then the x-coordinate of the midpoint will also be the same value.

This is true for the y-coordinates as well. The midpoint of (x1, y) and (x2, y) is at the average of the x-coordinates

and y or at , and the midpoint of (x, y1) and (x, y2) is at .

c. When the x- and y-coordinates are both different, the midpoint should be at the average values of the coordinates,

or at .   d. Form a right triangle with the segment formed by the two points as the hypotenuse. Note that the other coordinateis (x2, y1) in the drawing. 

 

We know the Pythagorean Theorem is a2 + b

2 = c

2. We can solve this formula for c by taking the square root of

each side. So, . Now we can replace the variables with the lengths of each side. The length of

side a is x2 – x1. The length of side b is y2 – y1. The length of side c is now .

 

46. ERROR ANALYSIS  Wyatt and Dario are determining whether 36, 77, and 85 form a Pythagorean triple. Is eitherof them correct? Explain your reasoning.

SOLUTION:  Wyatt is correct. The square of the greatest value should be equal to the sum of the squares of the two smaller values.  Since this is the case, the numbers form a Pythagorean triple.

47. CCSS PERSEVERANCE  Find the value of x in the figure shown.

SOLUTION:  The figure can be separated into two right triangles. Let m represent the missing side length common to both right

triangles. From the Pythagorean Theorem, m2 = 2

2 + x

2 and 14

2 = 8

2 + m

2. Using substitution, you can find that 2

2 +

x2 = 14

2 – 8

2.

Solve for x.

48. REASONING  Provide a counterexample to the statement. Any two right triangles with the same hypotenuse have the same area.

SOLUTION:  Different lengths of a and b can produce the same value of c in the Pythagorean theorem.  

 

Sample answer: A right triangle with legs measuring 3 cm and 4 cm has a hypotenuse of 5 cm and an area of 6 cm2.

A right triangle with legs measuring 2 cm and  cm also has a hypotenuse of 5 cm, but its area is   cm2,

which is not equivalent to 6 cm2.

49. OPEN ENDED  Draw a right triangle that has a hypotenuse of  units.

SOLUTION:  Use the Pythagorean Theorem to select two side lengths for a and b with the given value of c.

 

50. WRITING IN MATH  Explain how to determine whether segments in three lengths could form a right triangle.

SOLUTION:  

From the converse of the Pythagorean Theorem, if a2 + b

2 = c

2 then a, b, and c are the lengths of the side of a right

triangle. So, check to see whether the square of the greatest number is equal to the sum of the squares of the other two numbers. Consider triangle with sides of 9, 12 and 15 and a triangle with sides of 7, 13 and 19. 

   

51. GEOMETRY  Find the missing length.

A  −17

B  −

C  

D  17

SOLUTION:  

The correct choice is C.

52. What is a solution of this equation?

F  0, 3 G  3 H  0 J  no solutions

SOLUTION:  

The correct choice is H.

53. SHORT RESPONSE  A plumber charges $40 for the first hour of each house call plus $8 for each additional half hour. If the plumber works for 4 hours, how much does he charge?

SOLUTION:  Let x = the total number of hours worked.

The plumber charges $88 for 4 hours of work.

54. Find the next term in the geometric sequence .

A  

B  

C   

D  

SOLUTION:  

The correct choice is B.

Solve each equation. Check your solution.

55. 

SOLUTION:  

Check.

56. 

SOLUTION:  

Check.

57. 

SOLUTION:  

Check.

58. 

SOLUTION:  

Check.

59. 

SOLUTION:  

Check.

60. 

SOLUTION:  

Check.

There is no real solution.

Simplify each expression.

61. 

SOLUTION:  

62. 

SOLUTION:  

63. 

SOLUTION:  

64. 

SOLUTION:  

65. 

SOLUTION:  

66. 

SOLUTION:  

Describe how the graph of each function is related to the graph of f (x) = x2.

67. g(x) = x2 − 8

SOLUTION:  

The graph of f (x) = x2 + c represents a vertical translation of the parent graph. The value of c is –8, and –8 < 0. If c

< 0, the graph of f (x) = x2 is translated  units down. Therefore, the graph of g(x) = x

2 – 8 is a translation of the

parent graph shifted down 8 units.

68. h(x) = x2

SOLUTION:  

The graph of f (x) = ax2 stretches or compresses the graph of f (x) = x

2 vertically. The value of a is , and 0 <  <

1. If 0 <  < 1, the graph of f (x) = x2 is compressed vertically. Therefore, the graph of h(x) = x

2 is the parent

graph compressed vertically.

69. h(x) = −x2 + 5

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is 5, and 5 > 0. If c > 0, the graph of f (x) = x2 is translated

 units up. Therefore, the graph of h(x) = −x2 + 5 is a translation of the parent graph shifted up 8 units and

reflected across the x-axis.

70. g(x) = (x + 10)2

SOLUTION:  

The graph of f (x) = (x – c)2 represents a horizontal translation of the parent graph. The value of c is –10, and –10 <

0. If c < 0, the graph of f (x) = (x – c)2

is translated  units left. Therefore, the graph of g(x) = (x + 10)2 is a

translation of the parent graph shifted left 10 units.

71. g(x) = −2x2

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = ax

2 stretches or

compresses the graph of f (x) = x2 vertically. The value of a is –2, and |–2| > 1. If  > 1, the graph of f (x) = x

2 is

stretched vertically. Therefore, the graph of g(x) = –2x2 is the parent graph reflected across the x-axis and stretched

vertically.

72. h(x) = −x2 −

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is , and < 0. If c < 0, the graph of f (x) = x2 is

translated  units down. Therefore, the graph of h(x) = −x2 is a translation of the parent graph shifted down

 units and reflected across the x-axis.

73. ROCK CLIMBING  While rock climbing, Damaris launches a grappling hook from a height of 6 feet with an initialupward velocity of 56 feet per second. The hook just misses the stone ledge that she wants to scale. As it falls, the hook anchors on a ledge 30 feet above the ground. How long was the hook in the air?

SOLUTION:  

A half second after she throws the hook, it is 30 feet in the air. The hook continues up, then drops back down to the height of 30 feet 3 seconds after the throw. The hook was in the air for 3 seconds.

Find each product.74. (b + 8)(b + 2)

SOLUTION:  

75. (x − 4)(x − 9)

SOLUTION:  

76. (y + 4)(y − 8)

SOLUTION:  

77. (p + 2)(p − 10)

SOLUTION:  

78. (2w − 5)(w + 7)

SOLUTION:  

79. (8d + 3)(5d + 2)

SOLUTION:  

80. BUSINESS  The amount of money spent at West Outlet Mall continues to increase. The total T(x) in millions of

dollars can be estimated by the function T(x) = 12(1.12)x, where x is the number of years after it opened in 2005.

Find the amount of sales in 2015, 2016, and 2017.

SOLUTION:  

The sales for the mall in 2015 will be about $37.27 million; in 2016 will be about $41.74 million; and in 2017 will be about $46.75 million.

Solve each proportion.

81. 

SOLUTION:  

82. 

SOLUTION:  

83. 

SOLUTION:  

84. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 16

10-5 The Pythagorean Theorem

Page 17: Find each missing length. If necessary, round to the ......Find each missing length. If necessary, round to the nearest hundredth. 62/87,21 Use the Pythagorean Theorem, substituting

Find each missing length. If necessary, round to the nearest hundredth.

1. 

SOLUTION:  Use the Pythagorean Theorem, substituting 3 for a and 4 for b.

2. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 21 for c.

3. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for b and 19 for c.

4. 

SOLUTION:  Use the Pythagorean Theorem, substituting 8 for a and 12 for b.

5. BASEBALL  A baseball diamond is a square. The distance between consecutive bases is 90 feet.

a.  How far does a catcher have to throw the ball from home plate to second base? b.  How far does a third baseman throw the ball to the first baseman from a point in the baseline 15 feet from third to second base? c.  A base runner going from first to second base is 100 feet from home plate. How far is the runner from second base?

SOLUTION:  a. Use the Pythagorean Theorem, substituting 90 for a and 90 for b.

The catcher has to throw the ball about 127 ft from home plate to second base.   b. The diagram below illustrates the throw made by the third baseman.

The length of a is 90 – 15 or 75 feet. Find the length of the throw c by using the Pythagorean Theorem, substituting 75 for a and 90 for b.

The third baseman has to throw the ball about 117 feet to the first baseman.   c. The diagram below illustrates the position of the base runner.

Use the Pythagorean Theorem to find the length of side a by substituting 90 for b and 100 for c.

So, the base runner is about 44 feet from first base to second base. Therefore, the distance the base runner is from second is about 90 – 44 or 46 feet.  

Determine whether each set of measures can be the lengths of the sides of a right triangle.6. 8, 12, 16

SOLUTION:  

Since the measure of the longest side is 16, let c = 16, a = 8, and b = 12. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 8, 12, and 16 is not a right triangle.

7. 28, 45, 53

SOLUTION:  

Since the measure of the longest side is 53, let c = 53, a = 28, and b = 45. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 28, 45, and 53 is a right triangle.

8. 7, 24, 25

SOLUTION:  

Since the measure of the longest side is 25, let c = 25, a = 7, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 7, 24, and 25 is a right triangle.

9. 15, 25, 45

SOLUTION:  

Since the measure of the longest side is 45, let c = 45, a = 15, and b = 25. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 15, 25, and 45 is not a right triangle.

Find each missing length. If necessary, round to the nearest hundredth.

10. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for a and 14 for b.

11. 

SOLUTION:  Use the Pythagorean Theorem, substituting 2 for a and 12 for c.

12. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and 20 for b.

13. 

SOLUTION:  Use the Pythagorean Theorem, substituting 9 for b and 31 for c.

14. 

SOLUTION:  Use the Pythagorean Theorem, substituting 16 for a and 26 for c.

15. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and  for b.

16. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for b and 25 for c.

17. 

SOLUTION:  

Use the Pythagorean Theorem, substituting 5 for a and  for c.

18. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for b and  for c.

19. TELEVISION  Larry is buying an entertainment stand for his television. The diagonal of his television is 42 inches. The space for the television measures 30 inches by 36 inches. Will Larry’s television fit? Explain.

SOLUTION:  Use the Pythagorean Theorem, substituting 30 for a and 36 for b.

Yes; sample answer: The diagonal of the space in the TV stand is about 46.9 inches, which is greater than the diagonal of the television, so Larry’s TV will fit.

Determine whether each set of measures can be the lengths of the sides of a right triangle. Then determine whether they form a Pythagorean triple.

20. 9, 40, 41

SOLUTION:  

Since the measure of the longest side is 41, let c = 41, a = 9, and b = 40. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 9, 40, and 41 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

21. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = 3, and b = . Then determine whether c2 = a

2 +

b2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 3, , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

22. 

SOLUTION:  

Since the measure of the longest side is 12, let c = 12, a = 4, and b = . Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 4, , and 12 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

23. 

SOLUTION:  

Since the measure of the longest side is 14, let c = 14, a = , and b = 7. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths , 7, and 14 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

24. 8, 31.5, 32.5

SOLUTION:  

Since the measure of the longest side is 32.5, let c = 32.5, a = 8, and b = 31.5. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 8, 31.5, and 32.5 is a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number, but b and c are not whole numbers.

25. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = , and b = . Then determine whether c2 =

a2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths , , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

26. 18, 24, 30

SOLUTION:  

Since the measure of the longest side is 30, let c = 30, a = 18, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 18, 24, and 30 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

27. 36, 77, 85

SOLUTION:  

Since the measure of the longest side is 85, let c = 85, a = 36, and b = 77. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 36, 77, and 85 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

28. 17, 33, 98

SOLUTION:  Since the measure of the longest side is 98, let c = 98, a = 17, and b = 33. The length of c is greater than the sum of a and b, so this is not a triangle. 

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 17, 33, and 98 is not a triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

29. GEOMETRY  Refer to the triangle shown.

a.  What is a? b.  Find the area of the triangle.

SOLUTION:  a. Use the Pythagorean Theorem, substituting 11 for b and 23 for c.

b.

The area of the triangle is about 111.1 units2.

30. GARDENING  Khaliah wants to plant flowers in a triangular plot. She has three lengths of plastic garden edging that measure 8 feet, 15 feet, and 17 feet. Determine whether these pieces form a right triangle. Explain.

SOLUTION:  Yes; sample answer: The longest side is 17 feet so this has to be the hypotenuse.

82 + 15

2 = 17

2 so the pieces form a right triangle by the converse of the Pythagorean Theorem.

31. LADDER  Mr. Takeo is locked out of his house. The only open window is on the second floor. There is a bush along the edge of the house, so he places the neighbor’s ladder 10 feet from the house. To the nearest foot, what length of ladder does he need to reach the window?

SOLUTION:  Use the Pythagorean Theorem, substituting 10 for a and 28 for b.

He will need a 30-ft ladder to reach the window.

CCSS TOOLS  Find the length of the hypotenuse. Round to the nearest hundredth.

32. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for a and 10 for b.

33. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 7 for b.

34. DOLLHOUSE  Alonso is building a dollhouse for his sister’s birthday. The roof is 24 inches across and the slanted side is 16 inches long as shown. Find the height of the roof to the nearest tenth of an inch.

SOLUTION:  Use the Pythagorean Theorem, substituting 12 for b and 16 for c.

The height of the roof is 10.6 in.

35. GEOMETRY  Each side of a cube is 5 inches long. Find the length of a diagonal of the cube.

SOLUTION:  

Use the Pythagorean Theorem to find the diagonal of a side of the cube, substituting 5 for a and 5 for b.

Then, use the Pythagorean Theorem to find a diagonal of the cube, substituting 5 for a and  for b.

The length of a diagonal of the cube is about 8.66 in.

36. TOWN SQUARES  The largest town square in the world is Tiananmen Square in Beijing, China, covering 98 acres. a.  One square mile is 640 acres. Assuming that Tiananmen Square is a square, how many feet long is a side to the nearest foot? b.  To the nearest foot, what is the diagonal distance across Tiananmen Square?

SOLUTION:  a. First, use the conversion factor 1 square mile = 640 acres to convert the area of the square from acres to square miles.

So, 98 acres is 0.153125 square miles. Use dimensional analysis to convert this measure to square feet.  

  Next, use the formula for the area of a square to find the length of a side.

Therefore, a side of Tiananmen Square is about 2066 feet long.   b. Use the Pythagorean Theorem to find the length of the diagonal of the square, substituting 2066 for both a and b.

The diagonal distance across Tiananmen Square is about 2922 feet.

37. TRUCKS  Violeta needs to construct a ramp to roll a cart of moving boxes from her garage into the back of her truck. The truck is 6 feet from the garage. The back of the truck is 36 inches above the ground. How long does the ramp have to be?

SOLUTION:  First, rewrite 36 inches as 3 ft. Use the Pythagorean thereom, substituting 6 for a and 3 for b.

The ramp must be about 6.7 ft.

If c is the measure of the hypotenuse of a right triangle, find each missing measure. If necessary, round to the nearest hundredth.

38. a = x, b = x + 41, c = 85

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 36; b = 77

39. a = 8, b = x, c = x + 2

SOLUTION:  

b = 15; c = 17

40. a = 12, b = x − 2, c = x

SOLUTION:  

b = 35; c = 37

41. a = x, b = x + 7, c = 97

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 65; b = 72

42. a = x − 47, b = x, c = x + 2

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 16; b = 63; c = 65

43. a = x − 32, b = x − 1, c = x

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 9; b = 40; c = 41

44. GEOMETRY  A right triangle has one leg that is 8 inches shorter than the other leg. The hypotenuse is 30 inches long. Find the length of each leg.

SOLUTION:  

The length of each leg of the triangle is about 24.83 in. and about 16.83 in.

45. MULTIPLE REPRESENTATIONS In this problem, you will derive a method for finding the midpoint and length of a segment on the coordinate plane. a. Graphical Use a graph to find the lengths of the segments between (3, 2) and (8, 2) and between (4, 1) and (4, 9).Then find the midpoint of each segment. b. Logical Use what you learned in part a to write expressions for the lengths of the segments between (x1 , y) and

(x2 , y) and between (x, y1 ) and (x,  y2). What would be the midpoint of each segment?

c. Analytical Based on your results from part b, find the midpoint of the segment with endpoints at (x1, y1), and (x2,

y2).

d. Analytical Use the Pythagorean Theorem to write an expression for the distance between (x1, y1), and (x2, y2).

SOLUTION:  a.  From the graph, the length of the vertical segment is 9 – 1 or 8 units and the length of the horizontal line is 8 – 3 or 5 units.

The midpoints will be located in the middle of each segment, or the average of the coordinates. For the vertical segment, the value between 1 and 9 is 5, so the midpoint should be at (4, 5). For the horizontal segment, the value between 3 and 8 is 5.5, so the midpoint should be at (5.5, 2). b.  Distance: The length of the segment between (x1, y) and (x2, y) will be the absolute value of x1 – x2. The length

of the segment between (x, y1) and (x, y2) will be the absolute value of y1 – y2.

Midpoint: When the x-coordinates are identical, then the x-coordinate of the midpoint will also be the same value.

This is true for the y-coordinates as well. The midpoint of (x1, y) and (x2, y) is at the average of the x-coordinates

and y or at , and the midpoint of (x, y1) and (x, y2) is at .

c. When the x- and y-coordinates are both different, the midpoint should be at the average values of the coordinates,

or at .   d. Form a right triangle with the segment formed by the two points as the hypotenuse. Note that the other coordinateis (x2, y1) in the drawing. 

 

We know the Pythagorean Theorem is a2 + b

2 = c

2. We can solve this formula for c by taking the square root of

each side. So, . Now we can replace the variables with the lengths of each side. The length of

side a is x2 – x1. The length of side b is y2 – y1. The length of side c is now .

 

46. ERROR ANALYSIS  Wyatt and Dario are determining whether 36, 77, and 85 form a Pythagorean triple. Is eitherof them correct? Explain your reasoning.

SOLUTION:  Wyatt is correct. The square of the greatest value should be equal to the sum of the squares of the two smaller values.  Since this is the case, the numbers form a Pythagorean triple.

47. CCSS PERSEVERANCE  Find the value of x in the figure shown.

SOLUTION:  The figure can be separated into two right triangles. Let m represent the missing side length common to both right

triangles. From the Pythagorean Theorem, m2 = 2

2 + x

2 and 14

2 = 8

2 + m

2. Using substitution, you can find that 2

2 +

x2 = 14

2 – 8

2.

Solve for x.

48. REASONING  Provide a counterexample to the statement. Any two right triangles with the same hypotenuse have the same area.

SOLUTION:  Different lengths of a and b can produce the same value of c in the Pythagorean theorem.  

 

Sample answer: A right triangle with legs measuring 3 cm and 4 cm has a hypotenuse of 5 cm and an area of 6 cm2.

A right triangle with legs measuring 2 cm and  cm also has a hypotenuse of 5 cm, but its area is   cm2,

which is not equivalent to 6 cm2.

49. OPEN ENDED  Draw a right triangle that has a hypotenuse of  units.

SOLUTION:  Use the Pythagorean Theorem to select two side lengths for a and b with the given value of c.

 

50. WRITING IN MATH  Explain how to determine whether segments in three lengths could form a right triangle.

SOLUTION:  

From the converse of the Pythagorean Theorem, if a2 + b

2 = c

2 then a, b, and c are the lengths of the side of a right

triangle. So, check to see whether the square of the greatest number is equal to the sum of the squares of the other two numbers. Consider triangle with sides of 9, 12 and 15 and a triangle with sides of 7, 13 and 19. 

   

51. GEOMETRY  Find the missing length.

A  −17

B  −

C  

D  17

SOLUTION:  

The correct choice is C.

52. What is a solution of this equation?

F  0, 3 G  3 H  0 J  no solutions

SOLUTION:  

The correct choice is H.

53. SHORT RESPONSE  A plumber charges $40 for the first hour of each house call plus $8 for each additional half hour. If the plumber works for 4 hours, how much does he charge?

SOLUTION:  Let x = the total number of hours worked.

The plumber charges $88 for 4 hours of work.

54. Find the next term in the geometric sequence .

A  

B  

C   

D  

SOLUTION:  

The correct choice is B.

Solve each equation. Check your solution.

55. 

SOLUTION:  

Check.

56. 

SOLUTION:  

Check.

57. 

SOLUTION:  

Check.

58. 

SOLUTION:  

Check.

59. 

SOLUTION:  

Check.

60. 

SOLUTION:  

Check.

There is no real solution.

Simplify each expression.

61. 

SOLUTION:  

62. 

SOLUTION:  

63. 

SOLUTION:  

64. 

SOLUTION:  

65. 

SOLUTION:  

66. 

SOLUTION:  

Describe how the graph of each function is related to the graph of f (x) = x2.

67. g(x) = x2 − 8

SOLUTION:  

The graph of f (x) = x2 + c represents a vertical translation of the parent graph. The value of c is –8, and –8 < 0. If c

< 0, the graph of f (x) = x2 is translated  units down. Therefore, the graph of g(x) = x

2 – 8 is a translation of the

parent graph shifted down 8 units.

68. h(x) = x2

SOLUTION:  

The graph of f (x) = ax2 stretches or compresses the graph of f (x) = x

2 vertically. The value of a is , and 0 <  <

1. If 0 <  < 1, the graph of f (x) = x2 is compressed vertically. Therefore, the graph of h(x) = x

2 is the parent

graph compressed vertically.

69. h(x) = −x2 + 5

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is 5, and 5 > 0. If c > 0, the graph of f (x) = x2 is translated

 units up. Therefore, the graph of h(x) = −x2 + 5 is a translation of the parent graph shifted up 8 units and

reflected across the x-axis.

70. g(x) = (x + 10)2

SOLUTION:  

The graph of f (x) = (x – c)2 represents a horizontal translation of the parent graph. The value of c is –10, and –10 <

0. If c < 0, the graph of f (x) = (x – c)2

is translated  units left. Therefore, the graph of g(x) = (x + 10)2 is a

translation of the parent graph shifted left 10 units.

71. g(x) = −2x2

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = ax

2 stretches or

compresses the graph of f (x) = x2 vertically. The value of a is –2, and |–2| > 1. If  > 1, the graph of f (x) = x

2 is

stretched vertically. Therefore, the graph of g(x) = –2x2 is the parent graph reflected across the x-axis and stretched

vertically.

72. h(x) = −x2 −

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is , and < 0. If c < 0, the graph of f (x) = x2 is

translated  units down. Therefore, the graph of h(x) = −x2 is a translation of the parent graph shifted down

 units and reflected across the x-axis.

73. ROCK CLIMBING  While rock climbing, Damaris launches a grappling hook from a height of 6 feet with an initialupward velocity of 56 feet per second. The hook just misses the stone ledge that she wants to scale. As it falls, the hook anchors on a ledge 30 feet above the ground. How long was the hook in the air?

SOLUTION:  

A half second after she throws the hook, it is 30 feet in the air. The hook continues up, then drops back down to the height of 30 feet 3 seconds after the throw. The hook was in the air for 3 seconds.

Find each product.74. (b + 8)(b + 2)

SOLUTION:  

75. (x − 4)(x − 9)

SOLUTION:  

76. (y + 4)(y − 8)

SOLUTION:  

77. (p + 2)(p − 10)

SOLUTION:  

78. (2w − 5)(w + 7)

SOLUTION:  

79. (8d + 3)(5d + 2)

SOLUTION:  

80. BUSINESS  The amount of money spent at West Outlet Mall continues to increase. The total T(x) in millions of

dollars can be estimated by the function T(x) = 12(1.12)x, where x is the number of years after it opened in 2005.

Find the amount of sales in 2015, 2016, and 2017.

SOLUTION:  

The sales for the mall in 2015 will be about $37.27 million; in 2016 will be about $41.74 million; and in 2017 will be about $46.75 million.

Solve each proportion.

81. 

SOLUTION:  

82. 

SOLUTION:  

83. 

SOLUTION:  

84. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 17

10-5 The Pythagorean Theorem

Page 18: Find each missing length. If necessary, round to the ......Find each missing length. If necessary, round to the nearest hundredth. 62/87,21 Use the Pythagorean Theorem, substituting

Find each missing length. If necessary, round to the nearest hundredth.

1. 

SOLUTION:  Use the Pythagorean Theorem, substituting 3 for a and 4 for b.

2. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 21 for c.

3. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for b and 19 for c.

4. 

SOLUTION:  Use the Pythagorean Theorem, substituting 8 for a and 12 for b.

5. BASEBALL  A baseball diamond is a square. The distance between consecutive bases is 90 feet.

a.  How far does a catcher have to throw the ball from home plate to second base? b.  How far does a third baseman throw the ball to the first baseman from a point in the baseline 15 feet from third to second base? c.  A base runner going from first to second base is 100 feet from home plate. How far is the runner from second base?

SOLUTION:  a. Use the Pythagorean Theorem, substituting 90 for a and 90 for b.

The catcher has to throw the ball about 127 ft from home plate to second base.   b. The diagram below illustrates the throw made by the third baseman.

The length of a is 90 – 15 or 75 feet. Find the length of the throw c by using the Pythagorean Theorem, substituting 75 for a and 90 for b.

The third baseman has to throw the ball about 117 feet to the first baseman.   c. The diagram below illustrates the position of the base runner.

Use the Pythagorean Theorem to find the length of side a by substituting 90 for b and 100 for c.

So, the base runner is about 44 feet from first base to second base. Therefore, the distance the base runner is from second is about 90 – 44 or 46 feet.  

Determine whether each set of measures can be the lengths of the sides of a right triangle.6. 8, 12, 16

SOLUTION:  

Since the measure of the longest side is 16, let c = 16, a = 8, and b = 12. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 8, 12, and 16 is not a right triangle.

7. 28, 45, 53

SOLUTION:  

Since the measure of the longest side is 53, let c = 53, a = 28, and b = 45. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 28, 45, and 53 is a right triangle.

8. 7, 24, 25

SOLUTION:  

Since the measure of the longest side is 25, let c = 25, a = 7, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 7, 24, and 25 is a right triangle.

9. 15, 25, 45

SOLUTION:  

Since the measure of the longest side is 45, let c = 45, a = 15, and b = 25. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 15, 25, and 45 is not a right triangle.

Find each missing length. If necessary, round to the nearest hundredth.

10. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for a and 14 for b.

11. 

SOLUTION:  Use the Pythagorean Theorem, substituting 2 for a and 12 for c.

12. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and 20 for b.

13. 

SOLUTION:  Use the Pythagorean Theorem, substituting 9 for b and 31 for c.

14. 

SOLUTION:  Use the Pythagorean Theorem, substituting 16 for a and 26 for c.

15. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and  for b.

16. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for b and 25 for c.

17. 

SOLUTION:  

Use the Pythagorean Theorem, substituting 5 for a and  for c.

18. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for b and  for c.

19. TELEVISION  Larry is buying an entertainment stand for his television. The diagonal of his television is 42 inches. The space for the television measures 30 inches by 36 inches. Will Larry’s television fit? Explain.

SOLUTION:  Use the Pythagorean Theorem, substituting 30 for a and 36 for b.

Yes; sample answer: The diagonal of the space in the TV stand is about 46.9 inches, which is greater than the diagonal of the television, so Larry’s TV will fit.

Determine whether each set of measures can be the lengths of the sides of a right triangle. Then determine whether they form a Pythagorean triple.

20. 9, 40, 41

SOLUTION:  

Since the measure of the longest side is 41, let c = 41, a = 9, and b = 40. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 9, 40, and 41 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

21. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = 3, and b = . Then determine whether c2 = a

2 +

b2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 3, , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

22. 

SOLUTION:  

Since the measure of the longest side is 12, let c = 12, a = 4, and b = . Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 4, , and 12 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

23. 

SOLUTION:  

Since the measure of the longest side is 14, let c = 14, a = , and b = 7. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths , 7, and 14 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

24. 8, 31.5, 32.5

SOLUTION:  

Since the measure of the longest side is 32.5, let c = 32.5, a = 8, and b = 31.5. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 8, 31.5, and 32.5 is a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number, but b and c are not whole numbers.

25. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = , and b = . Then determine whether c2 =

a2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths , , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

26. 18, 24, 30

SOLUTION:  

Since the measure of the longest side is 30, let c = 30, a = 18, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 18, 24, and 30 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

27. 36, 77, 85

SOLUTION:  

Since the measure of the longest side is 85, let c = 85, a = 36, and b = 77. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 36, 77, and 85 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

28. 17, 33, 98

SOLUTION:  Since the measure of the longest side is 98, let c = 98, a = 17, and b = 33. The length of c is greater than the sum of a and b, so this is not a triangle. 

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 17, 33, and 98 is not a triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

29. GEOMETRY  Refer to the triangle shown.

a.  What is a? b.  Find the area of the triangle.

SOLUTION:  a. Use the Pythagorean Theorem, substituting 11 for b and 23 for c.

b.

The area of the triangle is about 111.1 units2.

30. GARDENING  Khaliah wants to plant flowers in a triangular plot. She has three lengths of plastic garden edging that measure 8 feet, 15 feet, and 17 feet. Determine whether these pieces form a right triangle. Explain.

SOLUTION:  Yes; sample answer: The longest side is 17 feet so this has to be the hypotenuse.

82 + 15

2 = 17

2 so the pieces form a right triangle by the converse of the Pythagorean Theorem.

31. LADDER  Mr. Takeo is locked out of his house. The only open window is on the second floor. There is a bush along the edge of the house, so he places the neighbor’s ladder 10 feet from the house. To the nearest foot, what length of ladder does he need to reach the window?

SOLUTION:  Use the Pythagorean Theorem, substituting 10 for a and 28 for b.

He will need a 30-ft ladder to reach the window.

CCSS TOOLS  Find the length of the hypotenuse. Round to the nearest hundredth.

32. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for a and 10 for b.

33. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 7 for b.

34. DOLLHOUSE  Alonso is building a dollhouse for his sister’s birthday. The roof is 24 inches across and the slanted side is 16 inches long as shown. Find the height of the roof to the nearest tenth of an inch.

SOLUTION:  Use the Pythagorean Theorem, substituting 12 for b and 16 for c.

The height of the roof is 10.6 in.

35. GEOMETRY  Each side of a cube is 5 inches long. Find the length of a diagonal of the cube.

SOLUTION:  

Use the Pythagorean Theorem to find the diagonal of a side of the cube, substituting 5 for a and 5 for b.

Then, use the Pythagorean Theorem to find a diagonal of the cube, substituting 5 for a and  for b.

The length of a diagonal of the cube is about 8.66 in.

36. TOWN SQUARES  The largest town square in the world is Tiananmen Square in Beijing, China, covering 98 acres. a.  One square mile is 640 acres. Assuming that Tiananmen Square is a square, how many feet long is a side to the nearest foot? b.  To the nearest foot, what is the diagonal distance across Tiananmen Square?

SOLUTION:  a. First, use the conversion factor 1 square mile = 640 acres to convert the area of the square from acres to square miles.

So, 98 acres is 0.153125 square miles. Use dimensional analysis to convert this measure to square feet.  

  Next, use the formula for the area of a square to find the length of a side.

Therefore, a side of Tiananmen Square is about 2066 feet long.   b. Use the Pythagorean Theorem to find the length of the diagonal of the square, substituting 2066 for both a and b.

The diagonal distance across Tiananmen Square is about 2922 feet.

37. TRUCKS  Violeta needs to construct a ramp to roll a cart of moving boxes from her garage into the back of her truck. The truck is 6 feet from the garage. The back of the truck is 36 inches above the ground. How long does the ramp have to be?

SOLUTION:  First, rewrite 36 inches as 3 ft. Use the Pythagorean thereom, substituting 6 for a and 3 for b.

The ramp must be about 6.7 ft.

If c is the measure of the hypotenuse of a right triangle, find each missing measure. If necessary, round to the nearest hundredth.

38. a = x, b = x + 41, c = 85

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 36; b = 77

39. a = 8, b = x, c = x + 2

SOLUTION:  

b = 15; c = 17

40. a = 12, b = x − 2, c = x

SOLUTION:  

b = 35; c = 37

41. a = x, b = x + 7, c = 97

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 65; b = 72

42. a = x − 47, b = x, c = x + 2

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 16; b = 63; c = 65

43. a = x − 32, b = x − 1, c = x

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 9; b = 40; c = 41

44. GEOMETRY  A right triangle has one leg that is 8 inches shorter than the other leg. The hypotenuse is 30 inches long. Find the length of each leg.

SOLUTION:  

The length of each leg of the triangle is about 24.83 in. and about 16.83 in.

45. MULTIPLE REPRESENTATIONS In this problem, you will derive a method for finding the midpoint and length of a segment on the coordinate plane. a. Graphical Use a graph to find the lengths of the segments between (3, 2) and (8, 2) and between (4, 1) and (4, 9).Then find the midpoint of each segment. b. Logical Use what you learned in part a to write expressions for the lengths of the segments between (x1 , y) and

(x2 , y) and between (x, y1 ) and (x,  y2). What would be the midpoint of each segment?

c. Analytical Based on your results from part b, find the midpoint of the segment with endpoints at (x1, y1), and (x2,

y2).

d. Analytical Use the Pythagorean Theorem to write an expression for the distance between (x1, y1), and (x2, y2).

SOLUTION:  a.  From the graph, the length of the vertical segment is 9 – 1 or 8 units and the length of the horizontal line is 8 – 3 or 5 units.

The midpoints will be located in the middle of each segment, or the average of the coordinates. For the vertical segment, the value between 1 and 9 is 5, so the midpoint should be at (4, 5). For the horizontal segment, the value between 3 and 8 is 5.5, so the midpoint should be at (5.5, 2). b.  Distance: The length of the segment between (x1, y) and (x2, y) will be the absolute value of x1 – x2. The length

of the segment between (x, y1) and (x, y2) will be the absolute value of y1 – y2.

Midpoint: When the x-coordinates are identical, then the x-coordinate of the midpoint will also be the same value.

This is true for the y-coordinates as well. The midpoint of (x1, y) and (x2, y) is at the average of the x-coordinates

and y or at , and the midpoint of (x, y1) and (x, y2) is at .

c. When the x- and y-coordinates are both different, the midpoint should be at the average values of the coordinates,

or at .   d. Form a right triangle with the segment formed by the two points as the hypotenuse. Note that the other coordinateis (x2, y1) in the drawing. 

 

We know the Pythagorean Theorem is a2 + b

2 = c

2. We can solve this formula for c by taking the square root of

each side. So, . Now we can replace the variables with the lengths of each side. The length of

side a is x2 – x1. The length of side b is y2 – y1. The length of side c is now .

 

46. ERROR ANALYSIS  Wyatt and Dario are determining whether 36, 77, and 85 form a Pythagorean triple. Is eitherof them correct? Explain your reasoning.

SOLUTION:  Wyatt is correct. The square of the greatest value should be equal to the sum of the squares of the two smaller values.  Since this is the case, the numbers form a Pythagorean triple.

47. CCSS PERSEVERANCE  Find the value of x in the figure shown.

SOLUTION:  The figure can be separated into two right triangles. Let m represent the missing side length common to both right

triangles. From the Pythagorean Theorem, m2 = 2

2 + x

2 and 14

2 = 8

2 + m

2. Using substitution, you can find that 2

2 +

x2 = 14

2 – 8

2.

Solve for x.

48. REASONING  Provide a counterexample to the statement. Any two right triangles with the same hypotenuse have the same area.

SOLUTION:  Different lengths of a and b can produce the same value of c in the Pythagorean theorem.  

 

Sample answer: A right triangle with legs measuring 3 cm and 4 cm has a hypotenuse of 5 cm and an area of 6 cm2.

A right triangle with legs measuring 2 cm and  cm also has a hypotenuse of 5 cm, but its area is   cm2,

which is not equivalent to 6 cm2.

49. OPEN ENDED  Draw a right triangle that has a hypotenuse of  units.

SOLUTION:  Use the Pythagorean Theorem to select two side lengths for a and b with the given value of c.

 

50. WRITING IN MATH  Explain how to determine whether segments in three lengths could form a right triangle.

SOLUTION:  

From the converse of the Pythagorean Theorem, if a2 + b

2 = c

2 then a, b, and c are the lengths of the side of a right

triangle. So, check to see whether the square of the greatest number is equal to the sum of the squares of the other two numbers. Consider triangle with sides of 9, 12 and 15 and a triangle with sides of 7, 13 and 19. 

   

51. GEOMETRY  Find the missing length.

A  −17

B  −

C  

D  17

SOLUTION:  

The correct choice is C.

52. What is a solution of this equation?

F  0, 3 G  3 H  0 J  no solutions

SOLUTION:  

The correct choice is H.

53. SHORT RESPONSE  A plumber charges $40 for the first hour of each house call plus $8 for each additional half hour. If the plumber works for 4 hours, how much does he charge?

SOLUTION:  Let x = the total number of hours worked.

The plumber charges $88 for 4 hours of work.

54. Find the next term in the geometric sequence .

A  

B  

C   

D  

SOLUTION:  

The correct choice is B.

Solve each equation. Check your solution.

55. 

SOLUTION:  

Check.

56. 

SOLUTION:  

Check.

57. 

SOLUTION:  

Check.

58. 

SOLUTION:  

Check.

59. 

SOLUTION:  

Check.

60. 

SOLUTION:  

Check.

There is no real solution.

Simplify each expression.

61. 

SOLUTION:  

62. 

SOLUTION:  

63. 

SOLUTION:  

64. 

SOLUTION:  

65. 

SOLUTION:  

66. 

SOLUTION:  

Describe how the graph of each function is related to the graph of f (x) = x2.

67. g(x) = x2 − 8

SOLUTION:  

The graph of f (x) = x2 + c represents a vertical translation of the parent graph. The value of c is –8, and –8 < 0. If c

< 0, the graph of f (x) = x2 is translated  units down. Therefore, the graph of g(x) = x

2 – 8 is a translation of the

parent graph shifted down 8 units.

68. h(x) = x2

SOLUTION:  

The graph of f (x) = ax2 stretches or compresses the graph of f (x) = x

2 vertically. The value of a is , and 0 <  <

1. If 0 <  < 1, the graph of f (x) = x2 is compressed vertically. Therefore, the graph of h(x) = x

2 is the parent

graph compressed vertically.

69. h(x) = −x2 + 5

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is 5, and 5 > 0. If c > 0, the graph of f (x) = x2 is translated

 units up. Therefore, the graph of h(x) = −x2 + 5 is a translation of the parent graph shifted up 8 units and

reflected across the x-axis.

70. g(x) = (x + 10)2

SOLUTION:  

The graph of f (x) = (x – c)2 represents a horizontal translation of the parent graph. The value of c is –10, and –10 <

0. If c < 0, the graph of f (x) = (x – c)2

is translated  units left. Therefore, the graph of g(x) = (x + 10)2 is a

translation of the parent graph shifted left 10 units.

71. g(x) = −2x2

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = ax

2 stretches or

compresses the graph of f (x) = x2 vertically. The value of a is –2, and |–2| > 1. If  > 1, the graph of f (x) = x

2 is

stretched vertically. Therefore, the graph of g(x) = –2x2 is the parent graph reflected across the x-axis and stretched

vertically.

72. h(x) = −x2 −

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is , and < 0. If c < 0, the graph of f (x) = x2 is

translated  units down. Therefore, the graph of h(x) = −x2 is a translation of the parent graph shifted down

 units and reflected across the x-axis.

73. ROCK CLIMBING  While rock climbing, Damaris launches a grappling hook from a height of 6 feet with an initialupward velocity of 56 feet per second. The hook just misses the stone ledge that she wants to scale. As it falls, the hook anchors on a ledge 30 feet above the ground. How long was the hook in the air?

SOLUTION:  

A half second after she throws the hook, it is 30 feet in the air. The hook continues up, then drops back down to the height of 30 feet 3 seconds after the throw. The hook was in the air for 3 seconds.

Find each product.74. (b + 8)(b + 2)

SOLUTION:  

75. (x − 4)(x − 9)

SOLUTION:  

76. (y + 4)(y − 8)

SOLUTION:  

77. (p + 2)(p − 10)

SOLUTION:  

78. (2w − 5)(w + 7)

SOLUTION:  

79. (8d + 3)(5d + 2)

SOLUTION:  

80. BUSINESS  The amount of money spent at West Outlet Mall continues to increase. The total T(x) in millions of

dollars can be estimated by the function T(x) = 12(1.12)x, where x is the number of years after it opened in 2005.

Find the amount of sales in 2015, 2016, and 2017.

SOLUTION:  

The sales for the mall in 2015 will be about $37.27 million; in 2016 will be about $41.74 million; and in 2017 will be about $46.75 million.

Solve each proportion.

81. 

SOLUTION:  

82. 

SOLUTION:  

83. 

SOLUTION:  

84. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 18

10-5 The Pythagorean Theorem

Page 19: Find each missing length. If necessary, round to the ......Find each missing length. If necessary, round to the nearest hundredth. 62/87,21 Use the Pythagorean Theorem, substituting

Find each missing length. If necessary, round to the nearest hundredth.

1. 

SOLUTION:  Use the Pythagorean Theorem, substituting 3 for a and 4 for b.

2. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 21 for c.

3. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for b and 19 for c.

4. 

SOLUTION:  Use the Pythagorean Theorem, substituting 8 for a and 12 for b.

5. BASEBALL  A baseball diamond is a square. The distance between consecutive bases is 90 feet.

a.  How far does a catcher have to throw the ball from home plate to second base? b.  How far does a third baseman throw the ball to the first baseman from a point in the baseline 15 feet from third to second base? c.  A base runner going from first to second base is 100 feet from home plate. How far is the runner from second base?

SOLUTION:  a. Use the Pythagorean Theorem, substituting 90 for a and 90 for b.

The catcher has to throw the ball about 127 ft from home plate to second base.   b. The diagram below illustrates the throw made by the third baseman.

The length of a is 90 – 15 or 75 feet. Find the length of the throw c by using the Pythagorean Theorem, substituting 75 for a and 90 for b.

The third baseman has to throw the ball about 117 feet to the first baseman.   c. The diagram below illustrates the position of the base runner.

Use the Pythagorean Theorem to find the length of side a by substituting 90 for b and 100 for c.

So, the base runner is about 44 feet from first base to second base. Therefore, the distance the base runner is from second is about 90 – 44 or 46 feet.  

Determine whether each set of measures can be the lengths of the sides of a right triangle.6. 8, 12, 16

SOLUTION:  

Since the measure of the longest side is 16, let c = 16, a = 8, and b = 12. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 8, 12, and 16 is not a right triangle.

7. 28, 45, 53

SOLUTION:  

Since the measure of the longest side is 53, let c = 53, a = 28, and b = 45. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 28, 45, and 53 is a right triangle.

8. 7, 24, 25

SOLUTION:  

Since the measure of the longest side is 25, let c = 25, a = 7, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 7, 24, and 25 is a right triangle.

9. 15, 25, 45

SOLUTION:  

Since the measure of the longest side is 45, let c = 45, a = 15, and b = 25. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 15, 25, and 45 is not a right triangle.

Find each missing length. If necessary, round to the nearest hundredth.

10. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for a and 14 for b.

11. 

SOLUTION:  Use the Pythagorean Theorem, substituting 2 for a and 12 for c.

12. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and 20 for b.

13. 

SOLUTION:  Use the Pythagorean Theorem, substituting 9 for b and 31 for c.

14. 

SOLUTION:  Use the Pythagorean Theorem, substituting 16 for a and 26 for c.

15. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and  for b.

16. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for b and 25 for c.

17. 

SOLUTION:  

Use the Pythagorean Theorem, substituting 5 for a and  for c.

18. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for b and  for c.

19. TELEVISION  Larry is buying an entertainment stand for his television. The diagonal of his television is 42 inches. The space for the television measures 30 inches by 36 inches. Will Larry’s television fit? Explain.

SOLUTION:  Use the Pythagorean Theorem, substituting 30 for a and 36 for b.

Yes; sample answer: The diagonal of the space in the TV stand is about 46.9 inches, which is greater than the diagonal of the television, so Larry’s TV will fit.

Determine whether each set of measures can be the lengths of the sides of a right triangle. Then determine whether they form a Pythagorean triple.

20. 9, 40, 41

SOLUTION:  

Since the measure of the longest side is 41, let c = 41, a = 9, and b = 40. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 9, 40, and 41 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

21. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = 3, and b = . Then determine whether c2 = a

2 +

b2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 3, , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

22. 

SOLUTION:  

Since the measure of the longest side is 12, let c = 12, a = 4, and b = . Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 4, , and 12 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

23. 

SOLUTION:  

Since the measure of the longest side is 14, let c = 14, a = , and b = 7. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths , 7, and 14 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

24. 8, 31.5, 32.5

SOLUTION:  

Since the measure of the longest side is 32.5, let c = 32.5, a = 8, and b = 31.5. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 8, 31.5, and 32.5 is a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number, but b and c are not whole numbers.

25. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = , and b = . Then determine whether c2 =

a2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths , , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

26. 18, 24, 30

SOLUTION:  

Since the measure of the longest side is 30, let c = 30, a = 18, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 18, 24, and 30 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

27. 36, 77, 85

SOLUTION:  

Since the measure of the longest side is 85, let c = 85, a = 36, and b = 77. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 36, 77, and 85 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

28. 17, 33, 98

SOLUTION:  Since the measure of the longest side is 98, let c = 98, a = 17, and b = 33. The length of c is greater than the sum of a and b, so this is not a triangle. 

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 17, 33, and 98 is not a triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

29. GEOMETRY  Refer to the triangle shown.

a.  What is a? b.  Find the area of the triangle.

SOLUTION:  a. Use the Pythagorean Theorem, substituting 11 for b and 23 for c.

b.

The area of the triangle is about 111.1 units2.

30. GARDENING  Khaliah wants to plant flowers in a triangular plot. She has three lengths of plastic garden edging that measure 8 feet, 15 feet, and 17 feet. Determine whether these pieces form a right triangle. Explain.

SOLUTION:  Yes; sample answer: The longest side is 17 feet so this has to be the hypotenuse.

82 + 15

2 = 17

2 so the pieces form a right triangle by the converse of the Pythagorean Theorem.

31. LADDER  Mr. Takeo is locked out of his house. The only open window is on the second floor. There is a bush along the edge of the house, so he places the neighbor’s ladder 10 feet from the house. To the nearest foot, what length of ladder does he need to reach the window?

SOLUTION:  Use the Pythagorean Theorem, substituting 10 for a and 28 for b.

He will need a 30-ft ladder to reach the window.

CCSS TOOLS  Find the length of the hypotenuse. Round to the nearest hundredth.

32. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for a and 10 for b.

33. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 7 for b.

34. DOLLHOUSE  Alonso is building a dollhouse for his sister’s birthday. The roof is 24 inches across and the slanted side is 16 inches long as shown. Find the height of the roof to the nearest tenth of an inch.

SOLUTION:  Use the Pythagorean Theorem, substituting 12 for b and 16 for c.

The height of the roof is 10.6 in.

35. GEOMETRY  Each side of a cube is 5 inches long. Find the length of a diagonal of the cube.

SOLUTION:  

Use the Pythagorean Theorem to find the diagonal of a side of the cube, substituting 5 for a and 5 for b.

Then, use the Pythagorean Theorem to find a diagonal of the cube, substituting 5 for a and  for b.

The length of a diagonal of the cube is about 8.66 in.

36. TOWN SQUARES  The largest town square in the world is Tiananmen Square in Beijing, China, covering 98 acres. a.  One square mile is 640 acres. Assuming that Tiananmen Square is a square, how many feet long is a side to the nearest foot? b.  To the nearest foot, what is the diagonal distance across Tiananmen Square?

SOLUTION:  a. First, use the conversion factor 1 square mile = 640 acres to convert the area of the square from acres to square miles.

So, 98 acres is 0.153125 square miles. Use dimensional analysis to convert this measure to square feet.  

  Next, use the formula for the area of a square to find the length of a side.

Therefore, a side of Tiananmen Square is about 2066 feet long.   b. Use the Pythagorean Theorem to find the length of the diagonal of the square, substituting 2066 for both a and b.

The diagonal distance across Tiananmen Square is about 2922 feet.

37. TRUCKS  Violeta needs to construct a ramp to roll a cart of moving boxes from her garage into the back of her truck. The truck is 6 feet from the garage. The back of the truck is 36 inches above the ground. How long does the ramp have to be?

SOLUTION:  First, rewrite 36 inches as 3 ft. Use the Pythagorean thereom, substituting 6 for a and 3 for b.

The ramp must be about 6.7 ft.

If c is the measure of the hypotenuse of a right triangle, find each missing measure. If necessary, round to the nearest hundredth.

38. a = x, b = x + 41, c = 85

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 36; b = 77

39. a = 8, b = x, c = x + 2

SOLUTION:  

b = 15; c = 17

40. a = 12, b = x − 2, c = x

SOLUTION:  

b = 35; c = 37

41. a = x, b = x + 7, c = 97

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 65; b = 72

42. a = x − 47, b = x, c = x + 2

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 16; b = 63; c = 65

43. a = x − 32, b = x − 1, c = x

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 9; b = 40; c = 41

44. GEOMETRY  A right triangle has one leg that is 8 inches shorter than the other leg. The hypotenuse is 30 inches long. Find the length of each leg.

SOLUTION:  

The length of each leg of the triangle is about 24.83 in. and about 16.83 in.

45. MULTIPLE REPRESENTATIONS In this problem, you will derive a method for finding the midpoint and length of a segment on the coordinate plane. a. Graphical Use a graph to find the lengths of the segments between (3, 2) and (8, 2) and between (4, 1) and (4, 9).Then find the midpoint of each segment. b. Logical Use what you learned in part a to write expressions for the lengths of the segments between (x1 , y) and

(x2 , y) and between (x, y1 ) and (x,  y2). What would be the midpoint of each segment?

c. Analytical Based on your results from part b, find the midpoint of the segment with endpoints at (x1, y1), and (x2,

y2).

d. Analytical Use the Pythagorean Theorem to write an expression for the distance between (x1, y1), and (x2, y2).

SOLUTION:  a.  From the graph, the length of the vertical segment is 9 – 1 or 8 units and the length of the horizontal line is 8 – 3 or 5 units.

The midpoints will be located in the middle of each segment, or the average of the coordinates. For the vertical segment, the value between 1 and 9 is 5, so the midpoint should be at (4, 5). For the horizontal segment, the value between 3 and 8 is 5.5, so the midpoint should be at (5.5, 2). b.  Distance: The length of the segment between (x1, y) and (x2, y) will be the absolute value of x1 – x2. The length

of the segment between (x, y1) and (x, y2) will be the absolute value of y1 – y2.

Midpoint: When the x-coordinates are identical, then the x-coordinate of the midpoint will also be the same value.

This is true for the y-coordinates as well. The midpoint of (x1, y) and (x2, y) is at the average of the x-coordinates

and y or at , and the midpoint of (x, y1) and (x, y2) is at .

c. When the x- and y-coordinates are both different, the midpoint should be at the average values of the coordinates,

or at .   d. Form a right triangle with the segment formed by the two points as the hypotenuse. Note that the other coordinateis (x2, y1) in the drawing. 

 

We know the Pythagorean Theorem is a2 + b

2 = c

2. We can solve this formula for c by taking the square root of

each side. So, . Now we can replace the variables with the lengths of each side. The length of

side a is x2 – x1. The length of side b is y2 – y1. The length of side c is now .

 

46. ERROR ANALYSIS  Wyatt and Dario are determining whether 36, 77, and 85 form a Pythagorean triple. Is eitherof them correct? Explain your reasoning.

SOLUTION:  Wyatt is correct. The square of the greatest value should be equal to the sum of the squares of the two smaller values.  Since this is the case, the numbers form a Pythagorean triple.

47. CCSS PERSEVERANCE  Find the value of x in the figure shown.

SOLUTION:  The figure can be separated into two right triangles. Let m represent the missing side length common to both right

triangles. From the Pythagorean Theorem, m2 = 2

2 + x

2 and 14

2 = 8

2 + m

2. Using substitution, you can find that 2

2 +

x2 = 14

2 – 8

2.

Solve for x.

48. REASONING  Provide a counterexample to the statement. Any two right triangles with the same hypotenuse have the same area.

SOLUTION:  Different lengths of a and b can produce the same value of c in the Pythagorean theorem.  

 

Sample answer: A right triangle with legs measuring 3 cm and 4 cm has a hypotenuse of 5 cm and an area of 6 cm2.

A right triangle with legs measuring 2 cm and  cm also has a hypotenuse of 5 cm, but its area is   cm2,

which is not equivalent to 6 cm2.

49. OPEN ENDED  Draw a right triangle that has a hypotenuse of  units.

SOLUTION:  Use the Pythagorean Theorem to select two side lengths for a and b with the given value of c.

 

50. WRITING IN MATH  Explain how to determine whether segments in three lengths could form a right triangle.

SOLUTION:  

From the converse of the Pythagorean Theorem, if a2 + b

2 = c

2 then a, b, and c are the lengths of the side of a right

triangle. So, check to see whether the square of the greatest number is equal to the sum of the squares of the other two numbers. Consider triangle with sides of 9, 12 and 15 and a triangle with sides of 7, 13 and 19. 

   

51. GEOMETRY  Find the missing length.

A  −17

B  −

C  

D  17

SOLUTION:  

The correct choice is C.

52. What is a solution of this equation?

F  0, 3 G  3 H  0 J  no solutions

SOLUTION:  

The correct choice is H.

53. SHORT RESPONSE  A plumber charges $40 for the first hour of each house call plus $8 for each additional half hour. If the plumber works for 4 hours, how much does he charge?

SOLUTION:  Let x = the total number of hours worked.

The plumber charges $88 for 4 hours of work.

54. Find the next term in the geometric sequence .

A  

B  

C   

D  

SOLUTION:  

The correct choice is B.

Solve each equation. Check your solution.

55. 

SOLUTION:  

Check.

56. 

SOLUTION:  

Check.

57. 

SOLUTION:  

Check.

58. 

SOLUTION:  

Check.

59. 

SOLUTION:  

Check.

60. 

SOLUTION:  

Check.

There is no real solution.

Simplify each expression.

61. 

SOLUTION:  

62. 

SOLUTION:  

63. 

SOLUTION:  

64. 

SOLUTION:  

65. 

SOLUTION:  

66. 

SOLUTION:  

Describe how the graph of each function is related to the graph of f (x) = x2.

67. g(x) = x2 − 8

SOLUTION:  

The graph of f (x) = x2 + c represents a vertical translation of the parent graph. The value of c is –8, and –8 < 0. If c

< 0, the graph of f (x) = x2 is translated  units down. Therefore, the graph of g(x) = x

2 – 8 is a translation of the

parent graph shifted down 8 units.

68. h(x) = x2

SOLUTION:  

The graph of f (x) = ax2 stretches or compresses the graph of f (x) = x

2 vertically. The value of a is , and 0 <  <

1. If 0 <  < 1, the graph of f (x) = x2 is compressed vertically. Therefore, the graph of h(x) = x

2 is the parent

graph compressed vertically.

69. h(x) = −x2 + 5

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is 5, and 5 > 0. If c > 0, the graph of f (x) = x2 is translated

 units up. Therefore, the graph of h(x) = −x2 + 5 is a translation of the parent graph shifted up 8 units and

reflected across the x-axis.

70. g(x) = (x + 10)2

SOLUTION:  

The graph of f (x) = (x – c)2 represents a horizontal translation of the parent graph. The value of c is –10, and –10 <

0. If c < 0, the graph of f (x) = (x – c)2

is translated  units left. Therefore, the graph of g(x) = (x + 10)2 is a

translation of the parent graph shifted left 10 units.

71. g(x) = −2x2

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = ax

2 stretches or

compresses the graph of f (x) = x2 vertically. The value of a is –2, and |–2| > 1. If  > 1, the graph of f (x) = x

2 is

stretched vertically. Therefore, the graph of g(x) = –2x2 is the parent graph reflected across the x-axis and stretched

vertically.

72. h(x) = −x2 −

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is , and < 0. If c < 0, the graph of f (x) = x2 is

translated  units down. Therefore, the graph of h(x) = −x2 is a translation of the parent graph shifted down

 units and reflected across the x-axis.

73. ROCK CLIMBING  While rock climbing, Damaris launches a grappling hook from a height of 6 feet with an initialupward velocity of 56 feet per second. The hook just misses the stone ledge that she wants to scale. As it falls, the hook anchors on a ledge 30 feet above the ground. How long was the hook in the air?

SOLUTION:  

A half second after she throws the hook, it is 30 feet in the air. The hook continues up, then drops back down to the height of 30 feet 3 seconds after the throw. The hook was in the air for 3 seconds.

Find each product.74. (b + 8)(b + 2)

SOLUTION:  

75. (x − 4)(x − 9)

SOLUTION:  

76. (y + 4)(y − 8)

SOLUTION:  

77. (p + 2)(p − 10)

SOLUTION:  

78. (2w − 5)(w + 7)

SOLUTION:  

79. (8d + 3)(5d + 2)

SOLUTION:  

80. BUSINESS  The amount of money spent at West Outlet Mall continues to increase. The total T(x) in millions of

dollars can be estimated by the function T(x) = 12(1.12)x, where x is the number of years after it opened in 2005.

Find the amount of sales in 2015, 2016, and 2017.

SOLUTION:  

The sales for the mall in 2015 will be about $37.27 million; in 2016 will be about $41.74 million; and in 2017 will be about $46.75 million.

Solve each proportion.

81. 

SOLUTION:  

82. 

SOLUTION:  

83. 

SOLUTION:  

84. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 19

10-5 The Pythagorean Theorem

Page 20: Find each missing length. If necessary, round to the ......Find each missing length. If necessary, round to the nearest hundredth. 62/87,21 Use the Pythagorean Theorem, substituting

Find each missing length. If necessary, round to the nearest hundredth.

1. 

SOLUTION:  Use the Pythagorean Theorem, substituting 3 for a and 4 for b.

2. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 21 for c.

3. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for b and 19 for c.

4. 

SOLUTION:  Use the Pythagorean Theorem, substituting 8 for a and 12 for b.

5. BASEBALL  A baseball diamond is a square. The distance between consecutive bases is 90 feet.

a.  How far does a catcher have to throw the ball from home plate to second base? b.  How far does a third baseman throw the ball to the first baseman from a point in the baseline 15 feet from third to second base? c.  A base runner going from first to second base is 100 feet from home plate. How far is the runner from second base?

SOLUTION:  a. Use the Pythagorean Theorem, substituting 90 for a and 90 for b.

The catcher has to throw the ball about 127 ft from home plate to second base.   b. The diagram below illustrates the throw made by the third baseman.

The length of a is 90 – 15 or 75 feet. Find the length of the throw c by using the Pythagorean Theorem, substituting 75 for a and 90 for b.

The third baseman has to throw the ball about 117 feet to the first baseman.   c. The diagram below illustrates the position of the base runner.

Use the Pythagorean Theorem to find the length of side a by substituting 90 for b and 100 for c.

So, the base runner is about 44 feet from first base to second base. Therefore, the distance the base runner is from second is about 90 – 44 or 46 feet.  

Determine whether each set of measures can be the lengths of the sides of a right triangle.6. 8, 12, 16

SOLUTION:  

Since the measure of the longest side is 16, let c = 16, a = 8, and b = 12. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 8, 12, and 16 is not a right triangle.

7. 28, 45, 53

SOLUTION:  

Since the measure of the longest side is 53, let c = 53, a = 28, and b = 45. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 28, 45, and 53 is a right triangle.

8. 7, 24, 25

SOLUTION:  

Since the measure of the longest side is 25, let c = 25, a = 7, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 7, 24, and 25 is a right triangle.

9. 15, 25, 45

SOLUTION:  

Since the measure of the longest side is 45, let c = 45, a = 15, and b = 25. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 15, 25, and 45 is not a right triangle.

Find each missing length. If necessary, round to the nearest hundredth.

10. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for a and 14 for b.

11. 

SOLUTION:  Use the Pythagorean Theorem, substituting 2 for a and 12 for c.

12. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and 20 for b.

13. 

SOLUTION:  Use the Pythagorean Theorem, substituting 9 for b and 31 for c.

14. 

SOLUTION:  Use the Pythagorean Theorem, substituting 16 for a and 26 for c.

15. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and  for b.

16. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for b and 25 for c.

17. 

SOLUTION:  

Use the Pythagorean Theorem, substituting 5 for a and  for c.

18. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for b and  for c.

19. TELEVISION  Larry is buying an entertainment stand for his television. The diagonal of his television is 42 inches. The space for the television measures 30 inches by 36 inches. Will Larry’s television fit? Explain.

SOLUTION:  Use the Pythagorean Theorem, substituting 30 for a and 36 for b.

Yes; sample answer: The diagonal of the space in the TV stand is about 46.9 inches, which is greater than the diagonal of the television, so Larry’s TV will fit.

Determine whether each set of measures can be the lengths of the sides of a right triangle. Then determine whether they form a Pythagorean triple.

20. 9, 40, 41

SOLUTION:  

Since the measure of the longest side is 41, let c = 41, a = 9, and b = 40. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 9, 40, and 41 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

21. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = 3, and b = . Then determine whether c2 = a

2 +

b2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 3, , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

22. 

SOLUTION:  

Since the measure of the longest side is 12, let c = 12, a = 4, and b = . Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 4, , and 12 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

23. 

SOLUTION:  

Since the measure of the longest side is 14, let c = 14, a = , and b = 7. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths , 7, and 14 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

24. 8, 31.5, 32.5

SOLUTION:  

Since the measure of the longest side is 32.5, let c = 32.5, a = 8, and b = 31.5. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 8, 31.5, and 32.5 is a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number, but b and c are not whole numbers.

25. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = , and b = . Then determine whether c2 =

a2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths , , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

26. 18, 24, 30

SOLUTION:  

Since the measure of the longest side is 30, let c = 30, a = 18, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 18, 24, and 30 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

27. 36, 77, 85

SOLUTION:  

Since the measure of the longest side is 85, let c = 85, a = 36, and b = 77. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 36, 77, and 85 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

28. 17, 33, 98

SOLUTION:  Since the measure of the longest side is 98, let c = 98, a = 17, and b = 33. The length of c is greater than the sum of a and b, so this is not a triangle. 

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 17, 33, and 98 is not a triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

29. GEOMETRY  Refer to the triangle shown.

a.  What is a? b.  Find the area of the triangle.

SOLUTION:  a. Use the Pythagorean Theorem, substituting 11 for b and 23 for c.

b.

The area of the triangle is about 111.1 units2.

30. GARDENING  Khaliah wants to plant flowers in a triangular plot. She has three lengths of plastic garden edging that measure 8 feet, 15 feet, and 17 feet. Determine whether these pieces form a right triangle. Explain.

SOLUTION:  Yes; sample answer: The longest side is 17 feet so this has to be the hypotenuse.

82 + 15

2 = 17

2 so the pieces form a right triangle by the converse of the Pythagorean Theorem.

31. LADDER  Mr. Takeo is locked out of his house. The only open window is on the second floor. There is a bush along the edge of the house, so he places the neighbor’s ladder 10 feet from the house. To the nearest foot, what length of ladder does he need to reach the window?

SOLUTION:  Use the Pythagorean Theorem, substituting 10 for a and 28 for b.

He will need a 30-ft ladder to reach the window.

CCSS TOOLS  Find the length of the hypotenuse. Round to the nearest hundredth.

32. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for a and 10 for b.

33. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 7 for b.

34. DOLLHOUSE  Alonso is building a dollhouse for his sister’s birthday. The roof is 24 inches across and the slanted side is 16 inches long as shown. Find the height of the roof to the nearest tenth of an inch.

SOLUTION:  Use the Pythagorean Theorem, substituting 12 for b and 16 for c.

The height of the roof is 10.6 in.

35. GEOMETRY  Each side of a cube is 5 inches long. Find the length of a diagonal of the cube.

SOLUTION:  

Use the Pythagorean Theorem to find the diagonal of a side of the cube, substituting 5 for a and 5 for b.

Then, use the Pythagorean Theorem to find a diagonal of the cube, substituting 5 for a and  for b.

The length of a diagonal of the cube is about 8.66 in.

36. TOWN SQUARES  The largest town square in the world is Tiananmen Square in Beijing, China, covering 98 acres. a.  One square mile is 640 acres. Assuming that Tiananmen Square is a square, how many feet long is a side to the nearest foot? b.  To the nearest foot, what is the diagonal distance across Tiananmen Square?

SOLUTION:  a. First, use the conversion factor 1 square mile = 640 acres to convert the area of the square from acres to square miles.

So, 98 acres is 0.153125 square miles. Use dimensional analysis to convert this measure to square feet.  

  Next, use the formula for the area of a square to find the length of a side.

Therefore, a side of Tiananmen Square is about 2066 feet long.   b. Use the Pythagorean Theorem to find the length of the diagonal of the square, substituting 2066 for both a and b.

The diagonal distance across Tiananmen Square is about 2922 feet.

37. TRUCKS  Violeta needs to construct a ramp to roll a cart of moving boxes from her garage into the back of her truck. The truck is 6 feet from the garage. The back of the truck is 36 inches above the ground. How long does the ramp have to be?

SOLUTION:  First, rewrite 36 inches as 3 ft. Use the Pythagorean thereom, substituting 6 for a and 3 for b.

The ramp must be about 6.7 ft.

If c is the measure of the hypotenuse of a right triangle, find each missing measure. If necessary, round to the nearest hundredth.

38. a = x, b = x + 41, c = 85

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 36; b = 77

39. a = 8, b = x, c = x + 2

SOLUTION:  

b = 15; c = 17

40. a = 12, b = x − 2, c = x

SOLUTION:  

b = 35; c = 37

41. a = x, b = x + 7, c = 97

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 65; b = 72

42. a = x − 47, b = x, c = x + 2

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 16; b = 63; c = 65

43. a = x − 32, b = x − 1, c = x

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 9; b = 40; c = 41

44. GEOMETRY  A right triangle has one leg that is 8 inches shorter than the other leg. The hypotenuse is 30 inches long. Find the length of each leg.

SOLUTION:  

The length of each leg of the triangle is about 24.83 in. and about 16.83 in.

45. MULTIPLE REPRESENTATIONS In this problem, you will derive a method for finding the midpoint and length of a segment on the coordinate plane. a. Graphical Use a graph to find the lengths of the segments between (3, 2) and (8, 2) and between (4, 1) and (4, 9).Then find the midpoint of each segment. b. Logical Use what you learned in part a to write expressions for the lengths of the segments between (x1 , y) and

(x2 , y) and between (x, y1 ) and (x,  y2). What would be the midpoint of each segment?

c. Analytical Based on your results from part b, find the midpoint of the segment with endpoints at (x1, y1), and (x2,

y2).

d. Analytical Use the Pythagorean Theorem to write an expression for the distance between (x1, y1), and (x2, y2).

SOLUTION:  a.  From the graph, the length of the vertical segment is 9 – 1 or 8 units and the length of the horizontal line is 8 – 3 or 5 units.

The midpoints will be located in the middle of each segment, or the average of the coordinates. For the vertical segment, the value between 1 and 9 is 5, so the midpoint should be at (4, 5). For the horizontal segment, the value between 3 and 8 is 5.5, so the midpoint should be at (5.5, 2). b.  Distance: The length of the segment between (x1, y) and (x2, y) will be the absolute value of x1 – x2. The length

of the segment between (x, y1) and (x, y2) will be the absolute value of y1 – y2.

Midpoint: When the x-coordinates are identical, then the x-coordinate of the midpoint will also be the same value.

This is true for the y-coordinates as well. The midpoint of (x1, y) and (x2, y) is at the average of the x-coordinates

and y or at , and the midpoint of (x, y1) and (x, y2) is at .

c. When the x- and y-coordinates are both different, the midpoint should be at the average values of the coordinates,

or at .   d. Form a right triangle with the segment formed by the two points as the hypotenuse. Note that the other coordinateis (x2, y1) in the drawing. 

 

We know the Pythagorean Theorem is a2 + b

2 = c

2. We can solve this formula for c by taking the square root of

each side. So, . Now we can replace the variables with the lengths of each side. The length of

side a is x2 – x1. The length of side b is y2 – y1. The length of side c is now .

 

46. ERROR ANALYSIS  Wyatt and Dario are determining whether 36, 77, and 85 form a Pythagorean triple. Is eitherof them correct? Explain your reasoning.

SOLUTION:  Wyatt is correct. The square of the greatest value should be equal to the sum of the squares of the two smaller values.  Since this is the case, the numbers form a Pythagorean triple.

47. CCSS PERSEVERANCE  Find the value of x in the figure shown.

SOLUTION:  The figure can be separated into two right triangles. Let m represent the missing side length common to both right

triangles. From the Pythagorean Theorem, m2 = 2

2 + x

2 and 14

2 = 8

2 + m

2. Using substitution, you can find that 2

2 +

x2 = 14

2 – 8

2.

Solve for x.

48. REASONING  Provide a counterexample to the statement. Any two right triangles with the same hypotenuse have the same area.

SOLUTION:  Different lengths of a and b can produce the same value of c in the Pythagorean theorem.  

 

Sample answer: A right triangle with legs measuring 3 cm and 4 cm has a hypotenuse of 5 cm and an area of 6 cm2.

A right triangle with legs measuring 2 cm and  cm also has a hypotenuse of 5 cm, but its area is   cm2,

which is not equivalent to 6 cm2.

49. OPEN ENDED  Draw a right triangle that has a hypotenuse of  units.

SOLUTION:  Use the Pythagorean Theorem to select two side lengths for a and b with the given value of c.

 

50. WRITING IN MATH  Explain how to determine whether segments in three lengths could form a right triangle.

SOLUTION:  

From the converse of the Pythagorean Theorem, if a2 + b

2 = c

2 then a, b, and c are the lengths of the side of a right

triangle. So, check to see whether the square of the greatest number is equal to the sum of the squares of the other two numbers. Consider triangle with sides of 9, 12 and 15 and a triangle with sides of 7, 13 and 19. 

   

51. GEOMETRY  Find the missing length.

A  −17

B  −

C  

D  17

SOLUTION:  

The correct choice is C.

52. What is a solution of this equation?

F  0, 3 G  3 H  0 J  no solutions

SOLUTION:  

The correct choice is H.

53. SHORT RESPONSE  A plumber charges $40 for the first hour of each house call plus $8 for each additional half hour. If the plumber works for 4 hours, how much does he charge?

SOLUTION:  Let x = the total number of hours worked.

The plumber charges $88 for 4 hours of work.

54. Find the next term in the geometric sequence .

A  

B  

C   

D  

SOLUTION:  

The correct choice is B.

Solve each equation. Check your solution.

55. 

SOLUTION:  

Check.

56. 

SOLUTION:  

Check.

57. 

SOLUTION:  

Check.

58. 

SOLUTION:  

Check.

59. 

SOLUTION:  

Check.

60. 

SOLUTION:  

Check.

There is no real solution.

Simplify each expression.

61. 

SOLUTION:  

62. 

SOLUTION:  

63. 

SOLUTION:  

64. 

SOLUTION:  

65. 

SOLUTION:  

66. 

SOLUTION:  

Describe how the graph of each function is related to the graph of f (x) = x2.

67. g(x) = x2 − 8

SOLUTION:  

The graph of f (x) = x2 + c represents a vertical translation of the parent graph. The value of c is –8, and –8 < 0. If c

< 0, the graph of f (x) = x2 is translated  units down. Therefore, the graph of g(x) = x

2 – 8 is a translation of the

parent graph shifted down 8 units.

68. h(x) = x2

SOLUTION:  

The graph of f (x) = ax2 stretches or compresses the graph of f (x) = x

2 vertically. The value of a is , and 0 <  <

1. If 0 <  < 1, the graph of f (x) = x2 is compressed vertically. Therefore, the graph of h(x) = x

2 is the parent

graph compressed vertically.

69. h(x) = −x2 + 5

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is 5, and 5 > 0. If c > 0, the graph of f (x) = x2 is translated

 units up. Therefore, the graph of h(x) = −x2 + 5 is a translation of the parent graph shifted up 8 units and

reflected across the x-axis.

70. g(x) = (x + 10)2

SOLUTION:  

The graph of f (x) = (x – c)2 represents a horizontal translation of the parent graph. The value of c is –10, and –10 <

0. If c < 0, the graph of f (x) = (x – c)2

is translated  units left. Therefore, the graph of g(x) = (x + 10)2 is a

translation of the parent graph shifted left 10 units.

71. g(x) = −2x2

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = ax

2 stretches or

compresses the graph of f (x) = x2 vertically. The value of a is –2, and |–2| > 1. If  > 1, the graph of f (x) = x

2 is

stretched vertically. Therefore, the graph of g(x) = –2x2 is the parent graph reflected across the x-axis and stretched

vertically.

72. h(x) = −x2 −

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is , and < 0. If c < 0, the graph of f (x) = x2 is

translated  units down. Therefore, the graph of h(x) = −x2 is a translation of the parent graph shifted down

 units and reflected across the x-axis.

73. ROCK CLIMBING  While rock climbing, Damaris launches a grappling hook from a height of 6 feet with an initialupward velocity of 56 feet per second. The hook just misses the stone ledge that she wants to scale. As it falls, the hook anchors on a ledge 30 feet above the ground. How long was the hook in the air?

SOLUTION:  

A half second after she throws the hook, it is 30 feet in the air. The hook continues up, then drops back down to the height of 30 feet 3 seconds after the throw. The hook was in the air for 3 seconds.

Find each product.74. (b + 8)(b + 2)

SOLUTION:  

75. (x − 4)(x − 9)

SOLUTION:  

76. (y + 4)(y − 8)

SOLUTION:  

77. (p + 2)(p − 10)

SOLUTION:  

78. (2w − 5)(w + 7)

SOLUTION:  

79. (8d + 3)(5d + 2)

SOLUTION:  

80. BUSINESS  The amount of money spent at West Outlet Mall continues to increase. The total T(x) in millions of

dollars can be estimated by the function T(x) = 12(1.12)x, where x is the number of years after it opened in 2005.

Find the amount of sales in 2015, 2016, and 2017.

SOLUTION:  

The sales for the mall in 2015 will be about $37.27 million; in 2016 will be about $41.74 million; and in 2017 will be about $46.75 million.

Solve each proportion.

81. 

SOLUTION:  

82. 

SOLUTION:  

83. 

SOLUTION:  

84. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 20

10-5 The Pythagorean Theorem

Page 21: Find each missing length. If necessary, round to the ......Find each missing length. If necessary, round to the nearest hundredth. 62/87,21 Use the Pythagorean Theorem, substituting

Find each missing length. If necessary, round to the nearest hundredth.

1. 

SOLUTION:  Use the Pythagorean Theorem, substituting 3 for a and 4 for b.

2. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 21 for c.

3. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for b and 19 for c.

4. 

SOLUTION:  Use the Pythagorean Theorem, substituting 8 for a and 12 for b.

5. BASEBALL  A baseball diamond is a square. The distance between consecutive bases is 90 feet.

a.  How far does a catcher have to throw the ball from home plate to second base? b.  How far does a third baseman throw the ball to the first baseman from a point in the baseline 15 feet from third to second base? c.  A base runner going from first to second base is 100 feet from home plate. How far is the runner from second base?

SOLUTION:  a. Use the Pythagorean Theorem, substituting 90 for a and 90 for b.

The catcher has to throw the ball about 127 ft from home plate to second base.   b. The diagram below illustrates the throw made by the third baseman.

The length of a is 90 – 15 or 75 feet. Find the length of the throw c by using the Pythagorean Theorem, substituting 75 for a and 90 for b.

The third baseman has to throw the ball about 117 feet to the first baseman.   c. The diagram below illustrates the position of the base runner.

Use the Pythagorean Theorem to find the length of side a by substituting 90 for b and 100 for c.

So, the base runner is about 44 feet from first base to second base. Therefore, the distance the base runner is from second is about 90 – 44 or 46 feet.  

Determine whether each set of measures can be the lengths of the sides of a right triangle.6. 8, 12, 16

SOLUTION:  

Since the measure of the longest side is 16, let c = 16, a = 8, and b = 12. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 8, 12, and 16 is not a right triangle.

7. 28, 45, 53

SOLUTION:  

Since the measure of the longest side is 53, let c = 53, a = 28, and b = 45. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 28, 45, and 53 is a right triangle.

8. 7, 24, 25

SOLUTION:  

Since the measure of the longest side is 25, let c = 25, a = 7, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 7, 24, and 25 is a right triangle.

9. 15, 25, 45

SOLUTION:  

Since the measure of the longest side is 45, let c = 45, a = 15, and b = 25. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 15, 25, and 45 is not a right triangle.

Find each missing length. If necessary, round to the nearest hundredth.

10. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for a and 14 for b.

11. 

SOLUTION:  Use the Pythagorean Theorem, substituting 2 for a and 12 for c.

12. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and 20 for b.

13. 

SOLUTION:  Use the Pythagorean Theorem, substituting 9 for b and 31 for c.

14. 

SOLUTION:  Use the Pythagorean Theorem, substituting 16 for a and 26 for c.

15. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and  for b.

16. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for b and 25 for c.

17. 

SOLUTION:  

Use the Pythagorean Theorem, substituting 5 for a and  for c.

18. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for b and  for c.

19. TELEVISION  Larry is buying an entertainment stand for his television. The diagonal of his television is 42 inches. The space for the television measures 30 inches by 36 inches. Will Larry’s television fit? Explain.

SOLUTION:  Use the Pythagorean Theorem, substituting 30 for a and 36 for b.

Yes; sample answer: The diagonal of the space in the TV stand is about 46.9 inches, which is greater than the diagonal of the television, so Larry’s TV will fit.

Determine whether each set of measures can be the lengths of the sides of a right triangle. Then determine whether they form a Pythagorean triple.

20. 9, 40, 41

SOLUTION:  

Since the measure of the longest side is 41, let c = 41, a = 9, and b = 40. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 9, 40, and 41 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

21. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = 3, and b = . Then determine whether c2 = a

2 +

b2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 3, , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

22. 

SOLUTION:  

Since the measure of the longest side is 12, let c = 12, a = 4, and b = . Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 4, , and 12 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

23. 

SOLUTION:  

Since the measure of the longest side is 14, let c = 14, a = , and b = 7. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths , 7, and 14 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

24. 8, 31.5, 32.5

SOLUTION:  

Since the measure of the longest side is 32.5, let c = 32.5, a = 8, and b = 31.5. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 8, 31.5, and 32.5 is a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number, but b and c are not whole numbers.

25. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = , and b = . Then determine whether c2 =

a2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths , , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

26. 18, 24, 30

SOLUTION:  

Since the measure of the longest side is 30, let c = 30, a = 18, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 18, 24, and 30 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

27. 36, 77, 85

SOLUTION:  

Since the measure of the longest side is 85, let c = 85, a = 36, and b = 77. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 36, 77, and 85 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

28. 17, 33, 98

SOLUTION:  Since the measure of the longest side is 98, let c = 98, a = 17, and b = 33. The length of c is greater than the sum of a and b, so this is not a triangle. 

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 17, 33, and 98 is not a triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

29. GEOMETRY  Refer to the triangle shown.

a.  What is a? b.  Find the area of the triangle.

SOLUTION:  a. Use the Pythagorean Theorem, substituting 11 for b and 23 for c.

b.

The area of the triangle is about 111.1 units2.

30. GARDENING  Khaliah wants to plant flowers in a triangular plot. She has three lengths of plastic garden edging that measure 8 feet, 15 feet, and 17 feet. Determine whether these pieces form a right triangle. Explain.

SOLUTION:  Yes; sample answer: The longest side is 17 feet so this has to be the hypotenuse.

82 + 15

2 = 17

2 so the pieces form a right triangle by the converse of the Pythagorean Theorem.

31. LADDER  Mr. Takeo is locked out of his house. The only open window is on the second floor. There is a bush along the edge of the house, so he places the neighbor’s ladder 10 feet from the house. To the nearest foot, what length of ladder does he need to reach the window?

SOLUTION:  Use the Pythagorean Theorem, substituting 10 for a and 28 for b.

He will need a 30-ft ladder to reach the window.

CCSS TOOLS  Find the length of the hypotenuse. Round to the nearest hundredth.

32. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for a and 10 for b.

33. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 7 for b.

34. DOLLHOUSE  Alonso is building a dollhouse for his sister’s birthday. The roof is 24 inches across and the slanted side is 16 inches long as shown. Find the height of the roof to the nearest tenth of an inch.

SOLUTION:  Use the Pythagorean Theorem, substituting 12 for b and 16 for c.

The height of the roof is 10.6 in.

35. GEOMETRY  Each side of a cube is 5 inches long. Find the length of a diagonal of the cube.

SOLUTION:  

Use the Pythagorean Theorem to find the diagonal of a side of the cube, substituting 5 for a and 5 for b.

Then, use the Pythagorean Theorem to find a diagonal of the cube, substituting 5 for a and  for b.

The length of a diagonal of the cube is about 8.66 in.

36. TOWN SQUARES  The largest town square in the world is Tiananmen Square in Beijing, China, covering 98 acres. a.  One square mile is 640 acres. Assuming that Tiananmen Square is a square, how many feet long is a side to the nearest foot? b.  To the nearest foot, what is the diagonal distance across Tiananmen Square?

SOLUTION:  a. First, use the conversion factor 1 square mile = 640 acres to convert the area of the square from acres to square miles.

So, 98 acres is 0.153125 square miles. Use dimensional analysis to convert this measure to square feet.  

  Next, use the formula for the area of a square to find the length of a side.

Therefore, a side of Tiananmen Square is about 2066 feet long.   b. Use the Pythagorean Theorem to find the length of the diagonal of the square, substituting 2066 for both a and b.

The diagonal distance across Tiananmen Square is about 2922 feet.

37. TRUCKS  Violeta needs to construct a ramp to roll a cart of moving boxes from her garage into the back of her truck. The truck is 6 feet from the garage. The back of the truck is 36 inches above the ground. How long does the ramp have to be?

SOLUTION:  First, rewrite 36 inches as 3 ft. Use the Pythagorean thereom, substituting 6 for a and 3 for b.

The ramp must be about 6.7 ft.

If c is the measure of the hypotenuse of a right triangle, find each missing measure. If necessary, round to the nearest hundredth.

38. a = x, b = x + 41, c = 85

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 36; b = 77

39. a = 8, b = x, c = x + 2

SOLUTION:  

b = 15; c = 17

40. a = 12, b = x − 2, c = x

SOLUTION:  

b = 35; c = 37

41. a = x, b = x + 7, c = 97

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 65; b = 72

42. a = x − 47, b = x, c = x + 2

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 16; b = 63; c = 65

43. a = x − 32, b = x − 1, c = x

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 9; b = 40; c = 41

44. GEOMETRY  A right triangle has one leg that is 8 inches shorter than the other leg. The hypotenuse is 30 inches long. Find the length of each leg.

SOLUTION:  

The length of each leg of the triangle is about 24.83 in. and about 16.83 in.

45. MULTIPLE REPRESENTATIONS In this problem, you will derive a method for finding the midpoint and length of a segment on the coordinate plane. a. Graphical Use a graph to find the lengths of the segments between (3, 2) and (8, 2) and between (4, 1) and (4, 9).Then find the midpoint of each segment. b. Logical Use what you learned in part a to write expressions for the lengths of the segments between (x1 , y) and

(x2 , y) and between (x, y1 ) and (x,  y2). What would be the midpoint of each segment?

c. Analytical Based on your results from part b, find the midpoint of the segment with endpoints at (x1, y1), and (x2,

y2).

d. Analytical Use the Pythagorean Theorem to write an expression for the distance between (x1, y1), and (x2, y2).

SOLUTION:  a.  From the graph, the length of the vertical segment is 9 – 1 or 8 units and the length of the horizontal line is 8 – 3 or 5 units.

The midpoints will be located in the middle of each segment, or the average of the coordinates. For the vertical segment, the value between 1 and 9 is 5, so the midpoint should be at (4, 5). For the horizontal segment, the value between 3 and 8 is 5.5, so the midpoint should be at (5.5, 2). b.  Distance: The length of the segment between (x1, y) and (x2, y) will be the absolute value of x1 – x2. The length

of the segment between (x, y1) and (x, y2) will be the absolute value of y1 – y2.

Midpoint: When the x-coordinates are identical, then the x-coordinate of the midpoint will also be the same value.

This is true for the y-coordinates as well. The midpoint of (x1, y) and (x2, y) is at the average of the x-coordinates

and y or at , and the midpoint of (x, y1) and (x, y2) is at .

c. When the x- and y-coordinates are both different, the midpoint should be at the average values of the coordinates,

or at .   d. Form a right triangle with the segment formed by the two points as the hypotenuse. Note that the other coordinateis (x2, y1) in the drawing. 

 

We know the Pythagorean Theorem is a2 + b

2 = c

2. We can solve this formula for c by taking the square root of

each side. So, . Now we can replace the variables with the lengths of each side. The length of

side a is x2 – x1. The length of side b is y2 – y1. The length of side c is now .

 

46. ERROR ANALYSIS  Wyatt and Dario are determining whether 36, 77, and 85 form a Pythagorean triple. Is eitherof them correct? Explain your reasoning.

SOLUTION:  Wyatt is correct. The square of the greatest value should be equal to the sum of the squares of the two smaller values.  Since this is the case, the numbers form a Pythagorean triple.

47. CCSS PERSEVERANCE  Find the value of x in the figure shown.

SOLUTION:  The figure can be separated into two right triangles. Let m represent the missing side length common to both right

triangles. From the Pythagorean Theorem, m2 = 2

2 + x

2 and 14

2 = 8

2 + m

2. Using substitution, you can find that 2

2 +

x2 = 14

2 – 8

2.

Solve for x.

48. REASONING  Provide a counterexample to the statement. Any two right triangles with the same hypotenuse have the same area.

SOLUTION:  Different lengths of a and b can produce the same value of c in the Pythagorean theorem.  

 

Sample answer: A right triangle with legs measuring 3 cm and 4 cm has a hypotenuse of 5 cm and an area of 6 cm2.

A right triangle with legs measuring 2 cm and  cm also has a hypotenuse of 5 cm, but its area is   cm2,

which is not equivalent to 6 cm2.

49. OPEN ENDED  Draw a right triangle that has a hypotenuse of  units.

SOLUTION:  Use the Pythagorean Theorem to select two side lengths for a and b with the given value of c.

 

50. WRITING IN MATH  Explain how to determine whether segments in three lengths could form a right triangle.

SOLUTION:  

From the converse of the Pythagorean Theorem, if a2 + b

2 = c

2 then a, b, and c are the lengths of the side of a right

triangle. So, check to see whether the square of the greatest number is equal to the sum of the squares of the other two numbers. Consider triangle with sides of 9, 12 and 15 and a triangle with sides of 7, 13 and 19. 

   

51. GEOMETRY  Find the missing length.

A  −17

B  −

C  

D  17

SOLUTION:  

The correct choice is C.

52. What is a solution of this equation?

F  0, 3 G  3 H  0 J  no solutions

SOLUTION:  

The correct choice is H.

53. SHORT RESPONSE  A plumber charges $40 for the first hour of each house call plus $8 for each additional half hour. If the plumber works for 4 hours, how much does he charge?

SOLUTION:  Let x = the total number of hours worked.

The plumber charges $88 for 4 hours of work.

54. Find the next term in the geometric sequence .

A  

B  

C   

D  

SOLUTION:  

The correct choice is B.

Solve each equation. Check your solution.

55. 

SOLUTION:  

Check.

56. 

SOLUTION:  

Check.

57. 

SOLUTION:  

Check.

58. 

SOLUTION:  

Check.

59. 

SOLUTION:  

Check.

60. 

SOLUTION:  

Check.

There is no real solution.

Simplify each expression.

61. 

SOLUTION:  

62. 

SOLUTION:  

63. 

SOLUTION:  

64. 

SOLUTION:  

65. 

SOLUTION:  

66. 

SOLUTION:  

Describe how the graph of each function is related to the graph of f (x) = x2.

67. g(x) = x2 − 8

SOLUTION:  

The graph of f (x) = x2 + c represents a vertical translation of the parent graph. The value of c is –8, and –8 < 0. If c

< 0, the graph of f (x) = x2 is translated  units down. Therefore, the graph of g(x) = x

2 – 8 is a translation of the

parent graph shifted down 8 units.

68. h(x) = x2

SOLUTION:  

The graph of f (x) = ax2 stretches or compresses the graph of f (x) = x

2 vertically. The value of a is , and 0 <  <

1. If 0 <  < 1, the graph of f (x) = x2 is compressed vertically. Therefore, the graph of h(x) = x

2 is the parent

graph compressed vertically.

69. h(x) = −x2 + 5

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is 5, and 5 > 0. If c > 0, the graph of f (x) = x2 is translated

 units up. Therefore, the graph of h(x) = −x2 + 5 is a translation of the parent graph shifted up 8 units and

reflected across the x-axis.

70. g(x) = (x + 10)2

SOLUTION:  

The graph of f (x) = (x – c)2 represents a horizontal translation of the parent graph. The value of c is –10, and –10 <

0. If c < 0, the graph of f (x) = (x – c)2

is translated  units left. Therefore, the graph of g(x) = (x + 10)2 is a

translation of the parent graph shifted left 10 units.

71. g(x) = −2x2

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = ax

2 stretches or

compresses the graph of f (x) = x2 vertically. The value of a is –2, and |–2| > 1. If  > 1, the graph of f (x) = x

2 is

stretched vertically. Therefore, the graph of g(x) = –2x2 is the parent graph reflected across the x-axis and stretched

vertically.

72. h(x) = −x2 −

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is , and < 0. If c < 0, the graph of f (x) = x2 is

translated  units down. Therefore, the graph of h(x) = −x2 is a translation of the parent graph shifted down

 units and reflected across the x-axis.

73. ROCK CLIMBING  While rock climbing, Damaris launches a grappling hook from a height of 6 feet with an initialupward velocity of 56 feet per second. The hook just misses the stone ledge that she wants to scale. As it falls, the hook anchors on a ledge 30 feet above the ground. How long was the hook in the air?

SOLUTION:  

A half second after she throws the hook, it is 30 feet in the air. The hook continues up, then drops back down to the height of 30 feet 3 seconds after the throw. The hook was in the air for 3 seconds.

Find each product.74. (b + 8)(b + 2)

SOLUTION:  

75. (x − 4)(x − 9)

SOLUTION:  

76. (y + 4)(y − 8)

SOLUTION:  

77. (p + 2)(p − 10)

SOLUTION:  

78. (2w − 5)(w + 7)

SOLUTION:  

79. (8d + 3)(5d + 2)

SOLUTION:  

80. BUSINESS  The amount of money spent at West Outlet Mall continues to increase. The total T(x) in millions of

dollars can be estimated by the function T(x) = 12(1.12)x, where x is the number of years after it opened in 2005.

Find the amount of sales in 2015, 2016, and 2017.

SOLUTION:  

The sales for the mall in 2015 will be about $37.27 million; in 2016 will be about $41.74 million; and in 2017 will be about $46.75 million.

Solve each proportion.

81. 

SOLUTION:  

82. 

SOLUTION:  

83. 

SOLUTION:  

84. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 21

10-5 The Pythagorean Theorem

Page 22: Find each missing length. If necessary, round to the ......Find each missing length. If necessary, round to the nearest hundredth. 62/87,21 Use the Pythagorean Theorem, substituting

Find each missing length. If necessary, round to the nearest hundredth.

1. 

SOLUTION:  Use the Pythagorean Theorem, substituting 3 for a and 4 for b.

2. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 21 for c.

3. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for b and 19 for c.

4. 

SOLUTION:  Use the Pythagorean Theorem, substituting 8 for a and 12 for b.

5. BASEBALL  A baseball diamond is a square. The distance between consecutive bases is 90 feet.

a.  How far does a catcher have to throw the ball from home plate to second base? b.  How far does a third baseman throw the ball to the first baseman from a point in the baseline 15 feet from third to second base? c.  A base runner going from first to second base is 100 feet from home plate. How far is the runner from second base?

SOLUTION:  a. Use the Pythagorean Theorem, substituting 90 for a and 90 for b.

The catcher has to throw the ball about 127 ft from home plate to second base.   b. The diagram below illustrates the throw made by the third baseman.

The length of a is 90 – 15 or 75 feet. Find the length of the throw c by using the Pythagorean Theorem, substituting 75 for a and 90 for b.

The third baseman has to throw the ball about 117 feet to the first baseman.   c. The diagram below illustrates the position of the base runner.

Use the Pythagorean Theorem to find the length of side a by substituting 90 for b and 100 for c.

So, the base runner is about 44 feet from first base to second base. Therefore, the distance the base runner is from second is about 90 – 44 or 46 feet.  

Determine whether each set of measures can be the lengths of the sides of a right triangle.6. 8, 12, 16

SOLUTION:  

Since the measure of the longest side is 16, let c = 16, a = 8, and b = 12. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 8, 12, and 16 is not a right triangle.

7. 28, 45, 53

SOLUTION:  

Since the measure of the longest side is 53, let c = 53, a = 28, and b = 45. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 28, 45, and 53 is a right triangle.

8. 7, 24, 25

SOLUTION:  

Since the measure of the longest side is 25, let c = 25, a = 7, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 7, 24, and 25 is a right triangle.

9. 15, 25, 45

SOLUTION:  

Since the measure of the longest side is 45, let c = 45, a = 15, and b = 25. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 15, 25, and 45 is not a right triangle.

Find each missing length. If necessary, round to the nearest hundredth.

10. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for a and 14 for b.

11. 

SOLUTION:  Use the Pythagorean Theorem, substituting 2 for a and 12 for c.

12. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and 20 for b.

13. 

SOLUTION:  Use the Pythagorean Theorem, substituting 9 for b and 31 for c.

14. 

SOLUTION:  Use the Pythagorean Theorem, substituting 16 for a and 26 for c.

15. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and  for b.

16. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for b and 25 for c.

17. 

SOLUTION:  

Use the Pythagorean Theorem, substituting 5 for a and  for c.

18. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for b and  for c.

19. TELEVISION  Larry is buying an entertainment stand for his television. The diagonal of his television is 42 inches. The space for the television measures 30 inches by 36 inches. Will Larry’s television fit? Explain.

SOLUTION:  Use the Pythagorean Theorem, substituting 30 for a and 36 for b.

Yes; sample answer: The diagonal of the space in the TV stand is about 46.9 inches, which is greater than the diagonal of the television, so Larry’s TV will fit.

Determine whether each set of measures can be the lengths of the sides of a right triangle. Then determine whether they form a Pythagorean triple.

20. 9, 40, 41

SOLUTION:  

Since the measure of the longest side is 41, let c = 41, a = 9, and b = 40. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 9, 40, and 41 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

21. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = 3, and b = . Then determine whether c2 = a

2 +

b2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 3, , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

22. 

SOLUTION:  

Since the measure of the longest side is 12, let c = 12, a = 4, and b = . Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 4, , and 12 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

23. 

SOLUTION:  

Since the measure of the longest side is 14, let c = 14, a = , and b = 7. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths , 7, and 14 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

24. 8, 31.5, 32.5

SOLUTION:  

Since the measure of the longest side is 32.5, let c = 32.5, a = 8, and b = 31.5. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 8, 31.5, and 32.5 is a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number, but b and c are not whole numbers.

25. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = , and b = . Then determine whether c2 =

a2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths , , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

26. 18, 24, 30

SOLUTION:  

Since the measure of the longest side is 30, let c = 30, a = 18, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 18, 24, and 30 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

27. 36, 77, 85

SOLUTION:  

Since the measure of the longest side is 85, let c = 85, a = 36, and b = 77. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 36, 77, and 85 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

28. 17, 33, 98

SOLUTION:  Since the measure of the longest side is 98, let c = 98, a = 17, and b = 33. The length of c is greater than the sum of a and b, so this is not a triangle. 

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 17, 33, and 98 is not a triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

29. GEOMETRY  Refer to the triangle shown.

a.  What is a? b.  Find the area of the triangle.

SOLUTION:  a. Use the Pythagorean Theorem, substituting 11 for b and 23 for c.

b.

The area of the triangle is about 111.1 units2.

30. GARDENING  Khaliah wants to plant flowers in a triangular plot. She has three lengths of plastic garden edging that measure 8 feet, 15 feet, and 17 feet. Determine whether these pieces form a right triangle. Explain.

SOLUTION:  Yes; sample answer: The longest side is 17 feet so this has to be the hypotenuse.

82 + 15

2 = 17

2 so the pieces form a right triangle by the converse of the Pythagorean Theorem.

31. LADDER  Mr. Takeo is locked out of his house. The only open window is on the second floor. There is a bush along the edge of the house, so he places the neighbor’s ladder 10 feet from the house. To the nearest foot, what length of ladder does he need to reach the window?

SOLUTION:  Use the Pythagorean Theorem, substituting 10 for a and 28 for b.

He will need a 30-ft ladder to reach the window.

CCSS TOOLS  Find the length of the hypotenuse. Round to the nearest hundredth.

32. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for a and 10 for b.

33. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 7 for b.

34. DOLLHOUSE  Alonso is building a dollhouse for his sister’s birthday. The roof is 24 inches across and the slanted side is 16 inches long as shown. Find the height of the roof to the nearest tenth of an inch.

SOLUTION:  Use the Pythagorean Theorem, substituting 12 for b and 16 for c.

The height of the roof is 10.6 in.

35. GEOMETRY  Each side of a cube is 5 inches long. Find the length of a diagonal of the cube.

SOLUTION:  

Use the Pythagorean Theorem to find the diagonal of a side of the cube, substituting 5 for a and 5 for b.

Then, use the Pythagorean Theorem to find a diagonal of the cube, substituting 5 for a and  for b.

The length of a diagonal of the cube is about 8.66 in.

36. TOWN SQUARES  The largest town square in the world is Tiananmen Square in Beijing, China, covering 98 acres. a.  One square mile is 640 acres. Assuming that Tiananmen Square is a square, how many feet long is a side to the nearest foot? b.  To the nearest foot, what is the diagonal distance across Tiananmen Square?

SOLUTION:  a. First, use the conversion factor 1 square mile = 640 acres to convert the area of the square from acres to square miles.

So, 98 acres is 0.153125 square miles. Use dimensional analysis to convert this measure to square feet.  

  Next, use the formula for the area of a square to find the length of a side.

Therefore, a side of Tiananmen Square is about 2066 feet long.   b. Use the Pythagorean Theorem to find the length of the diagonal of the square, substituting 2066 for both a and b.

The diagonal distance across Tiananmen Square is about 2922 feet.

37. TRUCKS  Violeta needs to construct a ramp to roll a cart of moving boxes from her garage into the back of her truck. The truck is 6 feet from the garage. The back of the truck is 36 inches above the ground. How long does the ramp have to be?

SOLUTION:  First, rewrite 36 inches as 3 ft. Use the Pythagorean thereom, substituting 6 for a and 3 for b.

The ramp must be about 6.7 ft.

If c is the measure of the hypotenuse of a right triangle, find each missing measure. If necessary, round to the nearest hundredth.

38. a = x, b = x + 41, c = 85

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 36; b = 77

39. a = 8, b = x, c = x + 2

SOLUTION:  

b = 15; c = 17

40. a = 12, b = x − 2, c = x

SOLUTION:  

b = 35; c = 37

41. a = x, b = x + 7, c = 97

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 65; b = 72

42. a = x − 47, b = x, c = x + 2

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 16; b = 63; c = 65

43. a = x − 32, b = x − 1, c = x

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 9; b = 40; c = 41

44. GEOMETRY  A right triangle has one leg that is 8 inches shorter than the other leg. The hypotenuse is 30 inches long. Find the length of each leg.

SOLUTION:  

The length of each leg of the triangle is about 24.83 in. and about 16.83 in.

45. MULTIPLE REPRESENTATIONS In this problem, you will derive a method for finding the midpoint and length of a segment on the coordinate plane. a. Graphical Use a graph to find the lengths of the segments between (3, 2) and (8, 2) and between (4, 1) and (4, 9).Then find the midpoint of each segment. b. Logical Use what you learned in part a to write expressions for the lengths of the segments between (x1 , y) and

(x2 , y) and between (x, y1 ) and (x,  y2). What would be the midpoint of each segment?

c. Analytical Based on your results from part b, find the midpoint of the segment with endpoints at (x1, y1), and (x2,

y2).

d. Analytical Use the Pythagorean Theorem to write an expression for the distance between (x1, y1), and (x2, y2).

SOLUTION:  a.  From the graph, the length of the vertical segment is 9 – 1 or 8 units and the length of the horizontal line is 8 – 3 or 5 units.

The midpoints will be located in the middle of each segment, or the average of the coordinates. For the vertical segment, the value between 1 and 9 is 5, so the midpoint should be at (4, 5). For the horizontal segment, the value between 3 and 8 is 5.5, so the midpoint should be at (5.5, 2). b.  Distance: The length of the segment between (x1, y) and (x2, y) will be the absolute value of x1 – x2. The length

of the segment between (x, y1) and (x, y2) will be the absolute value of y1 – y2.

Midpoint: When the x-coordinates are identical, then the x-coordinate of the midpoint will also be the same value.

This is true for the y-coordinates as well. The midpoint of (x1, y) and (x2, y) is at the average of the x-coordinates

and y or at , and the midpoint of (x, y1) and (x, y2) is at .

c. When the x- and y-coordinates are both different, the midpoint should be at the average values of the coordinates,

or at .   d. Form a right triangle with the segment formed by the two points as the hypotenuse. Note that the other coordinateis (x2, y1) in the drawing. 

 

We know the Pythagorean Theorem is a2 + b

2 = c

2. We can solve this formula for c by taking the square root of

each side. So, . Now we can replace the variables with the lengths of each side. The length of

side a is x2 – x1. The length of side b is y2 – y1. The length of side c is now .

 

46. ERROR ANALYSIS  Wyatt and Dario are determining whether 36, 77, and 85 form a Pythagorean triple. Is eitherof them correct? Explain your reasoning.

SOLUTION:  Wyatt is correct. The square of the greatest value should be equal to the sum of the squares of the two smaller values.  Since this is the case, the numbers form a Pythagorean triple.

47. CCSS PERSEVERANCE  Find the value of x in the figure shown.

SOLUTION:  The figure can be separated into two right triangles. Let m represent the missing side length common to both right

triangles. From the Pythagorean Theorem, m2 = 2

2 + x

2 and 14

2 = 8

2 + m

2. Using substitution, you can find that 2

2 +

x2 = 14

2 – 8

2.

Solve for x.

48. REASONING  Provide a counterexample to the statement. Any two right triangles with the same hypotenuse have the same area.

SOLUTION:  Different lengths of a and b can produce the same value of c in the Pythagorean theorem.  

 

Sample answer: A right triangle with legs measuring 3 cm and 4 cm has a hypotenuse of 5 cm and an area of 6 cm2.

A right triangle with legs measuring 2 cm and  cm also has a hypotenuse of 5 cm, but its area is   cm2,

which is not equivalent to 6 cm2.

49. OPEN ENDED  Draw a right triangle that has a hypotenuse of  units.

SOLUTION:  Use the Pythagorean Theorem to select two side lengths for a and b with the given value of c.

 

50. WRITING IN MATH  Explain how to determine whether segments in three lengths could form a right triangle.

SOLUTION:  

From the converse of the Pythagorean Theorem, if a2 + b

2 = c

2 then a, b, and c are the lengths of the side of a right

triangle. So, check to see whether the square of the greatest number is equal to the sum of the squares of the other two numbers. Consider triangle with sides of 9, 12 and 15 and a triangle with sides of 7, 13 and 19. 

   

51. GEOMETRY  Find the missing length.

A  −17

B  −

C  

D  17

SOLUTION:  

The correct choice is C.

52. What is a solution of this equation?

F  0, 3 G  3 H  0 J  no solutions

SOLUTION:  

The correct choice is H.

53. SHORT RESPONSE  A plumber charges $40 for the first hour of each house call plus $8 for each additional half hour. If the plumber works for 4 hours, how much does he charge?

SOLUTION:  Let x = the total number of hours worked.

The plumber charges $88 for 4 hours of work.

54. Find the next term in the geometric sequence .

A  

B  

C   

D  

SOLUTION:  

The correct choice is B.

Solve each equation. Check your solution.

55. 

SOLUTION:  

Check.

56. 

SOLUTION:  

Check.

57. 

SOLUTION:  

Check.

58. 

SOLUTION:  

Check.

59. 

SOLUTION:  

Check.

60. 

SOLUTION:  

Check.

There is no real solution.

Simplify each expression.

61. 

SOLUTION:  

62. 

SOLUTION:  

63. 

SOLUTION:  

64. 

SOLUTION:  

65. 

SOLUTION:  

66. 

SOLUTION:  

Describe how the graph of each function is related to the graph of f (x) = x2.

67. g(x) = x2 − 8

SOLUTION:  

The graph of f (x) = x2 + c represents a vertical translation of the parent graph. The value of c is –8, and –8 < 0. If c

< 0, the graph of f (x) = x2 is translated  units down. Therefore, the graph of g(x) = x

2 – 8 is a translation of the

parent graph shifted down 8 units.

68. h(x) = x2

SOLUTION:  

The graph of f (x) = ax2 stretches or compresses the graph of f (x) = x

2 vertically. The value of a is , and 0 <  <

1. If 0 <  < 1, the graph of f (x) = x2 is compressed vertically. Therefore, the graph of h(x) = x

2 is the parent

graph compressed vertically.

69. h(x) = −x2 + 5

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is 5, and 5 > 0. If c > 0, the graph of f (x) = x2 is translated

 units up. Therefore, the graph of h(x) = −x2 + 5 is a translation of the parent graph shifted up 8 units and

reflected across the x-axis.

70. g(x) = (x + 10)2

SOLUTION:  

The graph of f (x) = (x – c)2 represents a horizontal translation of the parent graph. The value of c is –10, and –10 <

0. If c < 0, the graph of f (x) = (x – c)2

is translated  units left. Therefore, the graph of g(x) = (x + 10)2 is a

translation of the parent graph shifted left 10 units.

71. g(x) = −2x2

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = ax

2 stretches or

compresses the graph of f (x) = x2 vertically. The value of a is –2, and |–2| > 1. If  > 1, the graph of f (x) = x

2 is

stretched vertically. Therefore, the graph of g(x) = –2x2 is the parent graph reflected across the x-axis and stretched

vertically.

72. h(x) = −x2 −

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is , and < 0. If c < 0, the graph of f (x) = x2 is

translated  units down. Therefore, the graph of h(x) = −x2 is a translation of the parent graph shifted down

 units and reflected across the x-axis.

73. ROCK CLIMBING  While rock climbing, Damaris launches a grappling hook from a height of 6 feet with an initialupward velocity of 56 feet per second. The hook just misses the stone ledge that she wants to scale. As it falls, the hook anchors on a ledge 30 feet above the ground. How long was the hook in the air?

SOLUTION:  

A half second after she throws the hook, it is 30 feet in the air. The hook continues up, then drops back down to the height of 30 feet 3 seconds after the throw. The hook was in the air for 3 seconds.

Find each product.74. (b + 8)(b + 2)

SOLUTION:  

75. (x − 4)(x − 9)

SOLUTION:  

76. (y + 4)(y − 8)

SOLUTION:  

77. (p + 2)(p − 10)

SOLUTION:  

78. (2w − 5)(w + 7)

SOLUTION:  

79. (8d + 3)(5d + 2)

SOLUTION:  

80. BUSINESS  The amount of money spent at West Outlet Mall continues to increase. The total T(x) in millions of

dollars can be estimated by the function T(x) = 12(1.12)x, where x is the number of years after it opened in 2005.

Find the amount of sales in 2015, 2016, and 2017.

SOLUTION:  

The sales for the mall in 2015 will be about $37.27 million; in 2016 will be about $41.74 million; and in 2017 will be about $46.75 million.

Solve each proportion.

81. 

SOLUTION:  

82. 

SOLUTION:  

83. 

SOLUTION:  

84. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 22

10-5 The Pythagorean Theorem

Page 23: Find each missing length. If necessary, round to the ......Find each missing length. If necessary, round to the nearest hundredth. 62/87,21 Use the Pythagorean Theorem, substituting

Find each missing length. If necessary, round to the nearest hundredth.

1. 

SOLUTION:  Use the Pythagorean Theorem, substituting 3 for a and 4 for b.

2. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 21 for c.

3. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for b and 19 for c.

4. 

SOLUTION:  Use the Pythagorean Theorem, substituting 8 for a and 12 for b.

5. BASEBALL  A baseball diamond is a square. The distance between consecutive bases is 90 feet.

a.  How far does a catcher have to throw the ball from home plate to second base? b.  How far does a third baseman throw the ball to the first baseman from a point in the baseline 15 feet from third to second base? c.  A base runner going from first to second base is 100 feet from home plate. How far is the runner from second base?

SOLUTION:  a. Use the Pythagorean Theorem, substituting 90 for a and 90 for b.

The catcher has to throw the ball about 127 ft from home plate to second base.   b. The diagram below illustrates the throw made by the third baseman.

The length of a is 90 – 15 or 75 feet. Find the length of the throw c by using the Pythagorean Theorem, substituting 75 for a and 90 for b.

The third baseman has to throw the ball about 117 feet to the first baseman.   c. The diagram below illustrates the position of the base runner.

Use the Pythagorean Theorem to find the length of side a by substituting 90 for b and 100 for c.

So, the base runner is about 44 feet from first base to second base. Therefore, the distance the base runner is from second is about 90 – 44 or 46 feet.  

Determine whether each set of measures can be the lengths of the sides of a right triangle.6. 8, 12, 16

SOLUTION:  

Since the measure of the longest side is 16, let c = 16, a = 8, and b = 12. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 8, 12, and 16 is not a right triangle.

7. 28, 45, 53

SOLUTION:  

Since the measure of the longest side is 53, let c = 53, a = 28, and b = 45. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 28, 45, and 53 is a right triangle.

8. 7, 24, 25

SOLUTION:  

Since the measure of the longest side is 25, let c = 25, a = 7, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 7, 24, and 25 is a right triangle.

9. 15, 25, 45

SOLUTION:  

Since the measure of the longest side is 45, let c = 45, a = 15, and b = 25. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 15, 25, and 45 is not a right triangle.

Find each missing length. If necessary, round to the nearest hundredth.

10. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for a and 14 for b.

11. 

SOLUTION:  Use the Pythagorean Theorem, substituting 2 for a and 12 for c.

12. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and 20 for b.

13. 

SOLUTION:  Use the Pythagorean Theorem, substituting 9 for b and 31 for c.

14. 

SOLUTION:  Use the Pythagorean Theorem, substituting 16 for a and 26 for c.

15. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and  for b.

16. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for b and 25 for c.

17. 

SOLUTION:  

Use the Pythagorean Theorem, substituting 5 for a and  for c.

18. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for b and  for c.

19. TELEVISION  Larry is buying an entertainment stand for his television. The diagonal of his television is 42 inches. The space for the television measures 30 inches by 36 inches. Will Larry’s television fit? Explain.

SOLUTION:  Use the Pythagorean Theorem, substituting 30 for a and 36 for b.

Yes; sample answer: The diagonal of the space in the TV stand is about 46.9 inches, which is greater than the diagonal of the television, so Larry’s TV will fit.

Determine whether each set of measures can be the lengths of the sides of a right triangle. Then determine whether they form a Pythagorean triple.

20. 9, 40, 41

SOLUTION:  

Since the measure of the longest side is 41, let c = 41, a = 9, and b = 40. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 9, 40, and 41 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

21. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = 3, and b = . Then determine whether c2 = a

2 +

b2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 3, , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

22. 

SOLUTION:  

Since the measure of the longest side is 12, let c = 12, a = 4, and b = . Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 4, , and 12 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

23. 

SOLUTION:  

Since the measure of the longest side is 14, let c = 14, a = , and b = 7. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths , 7, and 14 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

24. 8, 31.5, 32.5

SOLUTION:  

Since the measure of the longest side is 32.5, let c = 32.5, a = 8, and b = 31.5. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 8, 31.5, and 32.5 is a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number, but b and c are not whole numbers.

25. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = , and b = . Then determine whether c2 =

a2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths , , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

26. 18, 24, 30

SOLUTION:  

Since the measure of the longest side is 30, let c = 30, a = 18, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 18, 24, and 30 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

27. 36, 77, 85

SOLUTION:  

Since the measure of the longest side is 85, let c = 85, a = 36, and b = 77. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 36, 77, and 85 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

28. 17, 33, 98

SOLUTION:  Since the measure of the longest side is 98, let c = 98, a = 17, and b = 33. The length of c is greater than the sum of a and b, so this is not a triangle. 

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 17, 33, and 98 is not a triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

29. GEOMETRY  Refer to the triangle shown.

a.  What is a? b.  Find the area of the triangle.

SOLUTION:  a. Use the Pythagorean Theorem, substituting 11 for b and 23 for c.

b.

The area of the triangle is about 111.1 units2.

30. GARDENING  Khaliah wants to plant flowers in a triangular plot. She has three lengths of plastic garden edging that measure 8 feet, 15 feet, and 17 feet. Determine whether these pieces form a right triangle. Explain.

SOLUTION:  Yes; sample answer: The longest side is 17 feet so this has to be the hypotenuse.

82 + 15

2 = 17

2 so the pieces form a right triangle by the converse of the Pythagorean Theorem.

31. LADDER  Mr. Takeo is locked out of his house. The only open window is on the second floor. There is a bush along the edge of the house, so he places the neighbor’s ladder 10 feet from the house. To the nearest foot, what length of ladder does he need to reach the window?

SOLUTION:  Use the Pythagorean Theorem, substituting 10 for a and 28 for b.

He will need a 30-ft ladder to reach the window.

CCSS TOOLS  Find the length of the hypotenuse. Round to the nearest hundredth.

32. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for a and 10 for b.

33. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 7 for b.

34. DOLLHOUSE  Alonso is building a dollhouse for his sister’s birthday. The roof is 24 inches across and the slanted side is 16 inches long as shown. Find the height of the roof to the nearest tenth of an inch.

SOLUTION:  Use the Pythagorean Theorem, substituting 12 for b and 16 for c.

The height of the roof is 10.6 in.

35. GEOMETRY  Each side of a cube is 5 inches long. Find the length of a diagonal of the cube.

SOLUTION:  

Use the Pythagorean Theorem to find the diagonal of a side of the cube, substituting 5 for a and 5 for b.

Then, use the Pythagorean Theorem to find a diagonal of the cube, substituting 5 for a and  for b.

The length of a diagonal of the cube is about 8.66 in.

36. TOWN SQUARES  The largest town square in the world is Tiananmen Square in Beijing, China, covering 98 acres. a.  One square mile is 640 acres. Assuming that Tiananmen Square is a square, how many feet long is a side to the nearest foot? b.  To the nearest foot, what is the diagonal distance across Tiananmen Square?

SOLUTION:  a. First, use the conversion factor 1 square mile = 640 acres to convert the area of the square from acres to square miles.

So, 98 acres is 0.153125 square miles. Use dimensional analysis to convert this measure to square feet.  

  Next, use the formula for the area of a square to find the length of a side.

Therefore, a side of Tiananmen Square is about 2066 feet long.   b. Use the Pythagorean Theorem to find the length of the diagonal of the square, substituting 2066 for both a and b.

The diagonal distance across Tiananmen Square is about 2922 feet.

37. TRUCKS  Violeta needs to construct a ramp to roll a cart of moving boxes from her garage into the back of her truck. The truck is 6 feet from the garage. The back of the truck is 36 inches above the ground. How long does the ramp have to be?

SOLUTION:  First, rewrite 36 inches as 3 ft. Use the Pythagorean thereom, substituting 6 for a and 3 for b.

The ramp must be about 6.7 ft.

If c is the measure of the hypotenuse of a right triangle, find each missing measure. If necessary, round to the nearest hundredth.

38. a = x, b = x + 41, c = 85

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 36; b = 77

39. a = 8, b = x, c = x + 2

SOLUTION:  

b = 15; c = 17

40. a = 12, b = x − 2, c = x

SOLUTION:  

b = 35; c = 37

41. a = x, b = x + 7, c = 97

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 65; b = 72

42. a = x − 47, b = x, c = x + 2

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 16; b = 63; c = 65

43. a = x − 32, b = x − 1, c = x

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 9; b = 40; c = 41

44. GEOMETRY  A right triangle has one leg that is 8 inches shorter than the other leg. The hypotenuse is 30 inches long. Find the length of each leg.

SOLUTION:  

The length of each leg of the triangle is about 24.83 in. and about 16.83 in.

45. MULTIPLE REPRESENTATIONS In this problem, you will derive a method for finding the midpoint and length of a segment on the coordinate plane. a. Graphical Use a graph to find the lengths of the segments between (3, 2) and (8, 2) and between (4, 1) and (4, 9).Then find the midpoint of each segment. b. Logical Use what you learned in part a to write expressions for the lengths of the segments between (x1 , y) and

(x2 , y) and between (x, y1 ) and (x,  y2). What would be the midpoint of each segment?

c. Analytical Based on your results from part b, find the midpoint of the segment with endpoints at (x1, y1), and (x2,

y2).

d. Analytical Use the Pythagorean Theorem to write an expression for the distance between (x1, y1), and (x2, y2).

SOLUTION:  a.  From the graph, the length of the vertical segment is 9 – 1 or 8 units and the length of the horizontal line is 8 – 3 or 5 units.

The midpoints will be located in the middle of each segment, or the average of the coordinates. For the vertical segment, the value between 1 and 9 is 5, so the midpoint should be at (4, 5). For the horizontal segment, the value between 3 and 8 is 5.5, so the midpoint should be at (5.5, 2). b.  Distance: The length of the segment between (x1, y) and (x2, y) will be the absolute value of x1 – x2. The length

of the segment between (x, y1) and (x, y2) will be the absolute value of y1 – y2.

Midpoint: When the x-coordinates are identical, then the x-coordinate of the midpoint will also be the same value.

This is true for the y-coordinates as well. The midpoint of (x1, y) and (x2, y) is at the average of the x-coordinates

and y or at , and the midpoint of (x, y1) and (x, y2) is at .

c. When the x- and y-coordinates are both different, the midpoint should be at the average values of the coordinates,

or at .   d. Form a right triangle with the segment formed by the two points as the hypotenuse. Note that the other coordinateis (x2, y1) in the drawing. 

 

We know the Pythagorean Theorem is a2 + b

2 = c

2. We can solve this formula for c by taking the square root of

each side. So, . Now we can replace the variables with the lengths of each side. The length of

side a is x2 – x1. The length of side b is y2 – y1. The length of side c is now .

 

46. ERROR ANALYSIS  Wyatt and Dario are determining whether 36, 77, and 85 form a Pythagorean triple. Is eitherof them correct? Explain your reasoning.

SOLUTION:  Wyatt is correct. The square of the greatest value should be equal to the sum of the squares of the two smaller values.  Since this is the case, the numbers form a Pythagorean triple.

47. CCSS PERSEVERANCE  Find the value of x in the figure shown.

SOLUTION:  The figure can be separated into two right triangles. Let m represent the missing side length common to both right

triangles. From the Pythagorean Theorem, m2 = 2

2 + x

2 and 14

2 = 8

2 + m

2. Using substitution, you can find that 2

2 +

x2 = 14

2 – 8

2.

Solve for x.

48. REASONING  Provide a counterexample to the statement. Any two right triangles with the same hypotenuse have the same area.

SOLUTION:  Different lengths of a and b can produce the same value of c in the Pythagorean theorem.  

 

Sample answer: A right triangle with legs measuring 3 cm and 4 cm has a hypotenuse of 5 cm and an area of 6 cm2.

A right triangle with legs measuring 2 cm and  cm also has a hypotenuse of 5 cm, but its area is   cm2,

which is not equivalent to 6 cm2.

49. OPEN ENDED  Draw a right triangle that has a hypotenuse of  units.

SOLUTION:  Use the Pythagorean Theorem to select two side lengths for a and b with the given value of c.

 

50. WRITING IN MATH  Explain how to determine whether segments in three lengths could form a right triangle.

SOLUTION:  

From the converse of the Pythagorean Theorem, if a2 + b

2 = c

2 then a, b, and c are the lengths of the side of a right

triangle. So, check to see whether the square of the greatest number is equal to the sum of the squares of the other two numbers. Consider triangle with sides of 9, 12 and 15 and a triangle with sides of 7, 13 and 19. 

   

51. GEOMETRY  Find the missing length.

A  −17

B  −

C  

D  17

SOLUTION:  

The correct choice is C.

52. What is a solution of this equation?

F  0, 3 G  3 H  0 J  no solutions

SOLUTION:  

The correct choice is H.

53. SHORT RESPONSE  A plumber charges $40 for the first hour of each house call plus $8 for each additional half hour. If the plumber works for 4 hours, how much does he charge?

SOLUTION:  Let x = the total number of hours worked.

The plumber charges $88 for 4 hours of work.

54. Find the next term in the geometric sequence .

A  

B  

C   

D  

SOLUTION:  

The correct choice is B.

Solve each equation. Check your solution.

55. 

SOLUTION:  

Check.

56. 

SOLUTION:  

Check.

57. 

SOLUTION:  

Check.

58. 

SOLUTION:  

Check.

59. 

SOLUTION:  

Check.

60. 

SOLUTION:  

Check.

There is no real solution.

Simplify each expression.

61. 

SOLUTION:  

62. 

SOLUTION:  

63. 

SOLUTION:  

64. 

SOLUTION:  

65. 

SOLUTION:  

66. 

SOLUTION:  

Describe how the graph of each function is related to the graph of f (x) = x2.

67. g(x) = x2 − 8

SOLUTION:  

The graph of f (x) = x2 + c represents a vertical translation of the parent graph. The value of c is –8, and –8 < 0. If c

< 0, the graph of f (x) = x2 is translated  units down. Therefore, the graph of g(x) = x

2 – 8 is a translation of the

parent graph shifted down 8 units.

68. h(x) = x2

SOLUTION:  

The graph of f (x) = ax2 stretches or compresses the graph of f (x) = x

2 vertically. The value of a is , and 0 <  <

1. If 0 <  < 1, the graph of f (x) = x2 is compressed vertically. Therefore, the graph of h(x) = x

2 is the parent

graph compressed vertically.

69. h(x) = −x2 + 5

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is 5, and 5 > 0. If c > 0, the graph of f (x) = x2 is translated

 units up. Therefore, the graph of h(x) = −x2 + 5 is a translation of the parent graph shifted up 8 units and

reflected across the x-axis.

70. g(x) = (x + 10)2

SOLUTION:  

The graph of f (x) = (x – c)2 represents a horizontal translation of the parent graph. The value of c is –10, and –10 <

0. If c < 0, the graph of f (x) = (x – c)2

is translated  units left. Therefore, the graph of g(x) = (x + 10)2 is a

translation of the parent graph shifted left 10 units.

71. g(x) = −2x2

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = ax

2 stretches or

compresses the graph of f (x) = x2 vertically. The value of a is –2, and |–2| > 1. If  > 1, the graph of f (x) = x

2 is

stretched vertically. Therefore, the graph of g(x) = –2x2 is the parent graph reflected across the x-axis and stretched

vertically.

72. h(x) = −x2 −

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is , and < 0. If c < 0, the graph of f (x) = x2 is

translated  units down. Therefore, the graph of h(x) = −x2 is a translation of the parent graph shifted down

 units and reflected across the x-axis.

73. ROCK CLIMBING  While rock climbing, Damaris launches a grappling hook from a height of 6 feet with an initialupward velocity of 56 feet per second. The hook just misses the stone ledge that she wants to scale. As it falls, the hook anchors on a ledge 30 feet above the ground. How long was the hook in the air?

SOLUTION:  

A half second after she throws the hook, it is 30 feet in the air. The hook continues up, then drops back down to the height of 30 feet 3 seconds after the throw. The hook was in the air for 3 seconds.

Find each product.74. (b + 8)(b + 2)

SOLUTION:  

75. (x − 4)(x − 9)

SOLUTION:  

76. (y + 4)(y − 8)

SOLUTION:  

77. (p + 2)(p − 10)

SOLUTION:  

78. (2w − 5)(w + 7)

SOLUTION:  

79. (8d + 3)(5d + 2)

SOLUTION:  

80. BUSINESS  The amount of money spent at West Outlet Mall continues to increase. The total T(x) in millions of

dollars can be estimated by the function T(x) = 12(1.12)x, where x is the number of years after it opened in 2005.

Find the amount of sales in 2015, 2016, and 2017.

SOLUTION:  

The sales for the mall in 2015 will be about $37.27 million; in 2016 will be about $41.74 million; and in 2017 will be about $46.75 million.

Solve each proportion.

81. 

SOLUTION:  

82. 

SOLUTION:  

83. 

SOLUTION:  

84. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 23

10-5 The Pythagorean Theorem

Page 24: Find each missing length. If necessary, round to the ......Find each missing length. If necessary, round to the nearest hundredth. 62/87,21 Use the Pythagorean Theorem, substituting

Find each missing length. If necessary, round to the nearest hundredth.

1. 

SOLUTION:  Use the Pythagorean Theorem, substituting 3 for a and 4 for b.

2. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 21 for c.

3. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for b and 19 for c.

4. 

SOLUTION:  Use the Pythagorean Theorem, substituting 8 for a and 12 for b.

5. BASEBALL  A baseball diamond is a square. The distance between consecutive bases is 90 feet.

a.  How far does a catcher have to throw the ball from home plate to second base? b.  How far does a third baseman throw the ball to the first baseman from a point in the baseline 15 feet from third to second base? c.  A base runner going from first to second base is 100 feet from home plate. How far is the runner from second base?

SOLUTION:  a. Use the Pythagorean Theorem, substituting 90 for a and 90 for b.

The catcher has to throw the ball about 127 ft from home plate to second base.   b. The diagram below illustrates the throw made by the third baseman.

The length of a is 90 – 15 or 75 feet. Find the length of the throw c by using the Pythagorean Theorem, substituting 75 for a and 90 for b.

The third baseman has to throw the ball about 117 feet to the first baseman.   c. The diagram below illustrates the position of the base runner.

Use the Pythagorean Theorem to find the length of side a by substituting 90 for b and 100 for c.

So, the base runner is about 44 feet from first base to second base. Therefore, the distance the base runner is from second is about 90 – 44 or 46 feet.  

Determine whether each set of measures can be the lengths of the sides of a right triangle.6. 8, 12, 16

SOLUTION:  

Since the measure of the longest side is 16, let c = 16, a = 8, and b = 12. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 8, 12, and 16 is not a right triangle.

7. 28, 45, 53

SOLUTION:  

Since the measure of the longest side is 53, let c = 53, a = 28, and b = 45. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 28, 45, and 53 is a right triangle.

8. 7, 24, 25

SOLUTION:  

Since the measure of the longest side is 25, let c = 25, a = 7, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 7, 24, and 25 is a right triangle.

9. 15, 25, 45

SOLUTION:  

Since the measure of the longest side is 45, let c = 45, a = 15, and b = 25. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 15, 25, and 45 is not a right triangle.

Find each missing length. If necessary, round to the nearest hundredth.

10. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for a and 14 for b.

11. 

SOLUTION:  Use the Pythagorean Theorem, substituting 2 for a and 12 for c.

12. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and 20 for b.

13. 

SOLUTION:  Use the Pythagorean Theorem, substituting 9 for b and 31 for c.

14. 

SOLUTION:  Use the Pythagorean Theorem, substituting 16 for a and 26 for c.

15. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and  for b.

16. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for b and 25 for c.

17. 

SOLUTION:  

Use the Pythagorean Theorem, substituting 5 for a and  for c.

18. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for b and  for c.

19. TELEVISION  Larry is buying an entertainment stand for his television. The diagonal of his television is 42 inches. The space for the television measures 30 inches by 36 inches. Will Larry’s television fit? Explain.

SOLUTION:  Use the Pythagorean Theorem, substituting 30 for a and 36 for b.

Yes; sample answer: The diagonal of the space in the TV stand is about 46.9 inches, which is greater than the diagonal of the television, so Larry’s TV will fit.

Determine whether each set of measures can be the lengths of the sides of a right triangle. Then determine whether they form a Pythagorean triple.

20. 9, 40, 41

SOLUTION:  

Since the measure of the longest side is 41, let c = 41, a = 9, and b = 40. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 9, 40, and 41 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

21. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = 3, and b = . Then determine whether c2 = a

2 +

b2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 3, , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

22. 

SOLUTION:  

Since the measure of the longest side is 12, let c = 12, a = 4, and b = . Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 4, , and 12 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

23. 

SOLUTION:  

Since the measure of the longest side is 14, let c = 14, a = , and b = 7. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths , 7, and 14 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

24. 8, 31.5, 32.5

SOLUTION:  

Since the measure of the longest side is 32.5, let c = 32.5, a = 8, and b = 31.5. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 8, 31.5, and 32.5 is a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number, but b and c are not whole numbers.

25. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = , and b = . Then determine whether c2 =

a2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths , , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

26. 18, 24, 30

SOLUTION:  

Since the measure of the longest side is 30, let c = 30, a = 18, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 18, 24, and 30 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

27. 36, 77, 85

SOLUTION:  

Since the measure of the longest side is 85, let c = 85, a = 36, and b = 77. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 36, 77, and 85 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

28. 17, 33, 98

SOLUTION:  Since the measure of the longest side is 98, let c = 98, a = 17, and b = 33. The length of c is greater than the sum of a and b, so this is not a triangle. 

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 17, 33, and 98 is not a triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

29. GEOMETRY  Refer to the triangle shown.

a.  What is a? b.  Find the area of the triangle.

SOLUTION:  a. Use the Pythagorean Theorem, substituting 11 for b and 23 for c.

b.

The area of the triangle is about 111.1 units2.

30. GARDENING  Khaliah wants to plant flowers in a triangular plot. She has three lengths of plastic garden edging that measure 8 feet, 15 feet, and 17 feet. Determine whether these pieces form a right triangle. Explain.

SOLUTION:  Yes; sample answer: The longest side is 17 feet so this has to be the hypotenuse.

82 + 15

2 = 17

2 so the pieces form a right triangle by the converse of the Pythagorean Theorem.

31. LADDER  Mr. Takeo is locked out of his house. The only open window is on the second floor. There is a bush along the edge of the house, so he places the neighbor’s ladder 10 feet from the house. To the nearest foot, what length of ladder does he need to reach the window?

SOLUTION:  Use the Pythagorean Theorem, substituting 10 for a and 28 for b.

He will need a 30-ft ladder to reach the window.

CCSS TOOLS  Find the length of the hypotenuse. Round to the nearest hundredth.

32. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for a and 10 for b.

33. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 7 for b.

34. DOLLHOUSE  Alonso is building a dollhouse for his sister’s birthday. The roof is 24 inches across and the slanted side is 16 inches long as shown. Find the height of the roof to the nearest tenth of an inch.

SOLUTION:  Use the Pythagorean Theorem, substituting 12 for b and 16 for c.

The height of the roof is 10.6 in.

35. GEOMETRY  Each side of a cube is 5 inches long. Find the length of a diagonal of the cube.

SOLUTION:  

Use the Pythagorean Theorem to find the diagonal of a side of the cube, substituting 5 for a and 5 for b.

Then, use the Pythagorean Theorem to find a diagonal of the cube, substituting 5 for a and  for b.

The length of a diagonal of the cube is about 8.66 in.

36. TOWN SQUARES  The largest town square in the world is Tiananmen Square in Beijing, China, covering 98 acres. a.  One square mile is 640 acres. Assuming that Tiananmen Square is a square, how many feet long is a side to the nearest foot? b.  To the nearest foot, what is the diagonal distance across Tiananmen Square?

SOLUTION:  a. First, use the conversion factor 1 square mile = 640 acres to convert the area of the square from acres to square miles.

So, 98 acres is 0.153125 square miles. Use dimensional analysis to convert this measure to square feet.  

  Next, use the formula for the area of a square to find the length of a side.

Therefore, a side of Tiananmen Square is about 2066 feet long.   b. Use the Pythagorean Theorem to find the length of the diagonal of the square, substituting 2066 for both a and b.

The diagonal distance across Tiananmen Square is about 2922 feet.

37. TRUCKS  Violeta needs to construct a ramp to roll a cart of moving boxes from her garage into the back of her truck. The truck is 6 feet from the garage. The back of the truck is 36 inches above the ground. How long does the ramp have to be?

SOLUTION:  First, rewrite 36 inches as 3 ft. Use the Pythagorean thereom, substituting 6 for a and 3 for b.

The ramp must be about 6.7 ft.

If c is the measure of the hypotenuse of a right triangle, find each missing measure. If necessary, round to the nearest hundredth.

38. a = x, b = x + 41, c = 85

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 36; b = 77

39. a = 8, b = x, c = x + 2

SOLUTION:  

b = 15; c = 17

40. a = 12, b = x − 2, c = x

SOLUTION:  

b = 35; c = 37

41. a = x, b = x + 7, c = 97

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 65; b = 72

42. a = x − 47, b = x, c = x + 2

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 16; b = 63; c = 65

43. a = x − 32, b = x − 1, c = x

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 9; b = 40; c = 41

44. GEOMETRY  A right triangle has one leg that is 8 inches shorter than the other leg. The hypotenuse is 30 inches long. Find the length of each leg.

SOLUTION:  

The length of each leg of the triangle is about 24.83 in. and about 16.83 in.

45. MULTIPLE REPRESENTATIONS In this problem, you will derive a method for finding the midpoint and length of a segment on the coordinate plane. a. Graphical Use a graph to find the lengths of the segments between (3, 2) and (8, 2) and between (4, 1) and (4, 9).Then find the midpoint of each segment. b. Logical Use what you learned in part a to write expressions for the lengths of the segments between (x1 , y) and

(x2 , y) and between (x, y1 ) and (x,  y2). What would be the midpoint of each segment?

c. Analytical Based on your results from part b, find the midpoint of the segment with endpoints at (x1, y1), and (x2,

y2).

d. Analytical Use the Pythagorean Theorem to write an expression for the distance between (x1, y1), and (x2, y2).

SOLUTION:  a.  From the graph, the length of the vertical segment is 9 – 1 or 8 units and the length of the horizontal line is 8 – 3 or 5 units.

The midpoints will be located in the middle of each segment, or the average of the coordinates. For the vertical segment, the value between 1 and 9 is 5, so the midpoint should be at (4, 5). For the horizontal segment, the value between 3 and 8 is 5.5, so the midpoint should be at (5.5, 2). b.  Distance: The length of the segment between (x1, y) and (x2, y) will be the absolute value of x1 – x2. The length

of the segment between (x, y1) and (x, y2) will be the absolute value of y1 – y2.

Midpoint: When the x-coordinates are identical, then the x-coordinate of the midpoint will also be the same value.

This is true for the y-coordinates as well. The midpoint of (x1, y) and (x2, y) is at the average of the x-coordinates

and y or at , and the midpoint of (x, y1) and (x, y2) is at .

c. When the x- and y-coordinates are both different, the midpoint should be at the average values of the coordinates,

or at .   d. Form a right triangle with the segment formed by the two points as the hypotenuse. Note that the other coordinateis (x2, y1) in the drawing. 

 

We know the Pythagorean Theorem is a2 + b

2 = c

2. We can solve this formula for c by taking the square root of

each side. So, . Now we can replace the variables with the lengths of each side. The length of

side a is x2 – x1. The length of side b is y2 – y1. The length of side c is now .

 

46. ERROR ANALYSIS  Wyatt and Dario are determining whether 36, 77, and 85 form a Pythagorean triple. Is eitherof them correct? Explain your reasoning.

SOLUTION:  Wyatt is correct. The square of the greatest value should be equal to the sum of the squares of the two smaller values.  Since this is the case, the numbers form a Pythagorean triple.

47. CCSS PERSEVERANCE  Find the value of x in the figure shown.

SOLUTION:  The figure can be separated into two right triangles. Let m represent the missing side length common to both right

triangles. From the Pythagorean Theorem, m2 = 2

2 + x

2 and 14

2 = 8

2 + m

2. Using substitution, you can find that 2

2 +

x2 = 14

2 – 8

2.

Solve for x.

48. REASONING  Provide a counterexample to the statement. Any two right triangles with the same hypotenuse have the same area.

SOLUTION:  Different lengths of a and b can produce the same value of c in the Pythagorean theorem.  

 

Sample answer: A right triangle with legs measuring 3 cm and 4 cm has a hypotenuse of 5 cm and an area of 6 cm2.

A right triangle with legs measuring 2 cm and  cm also has a hypotenuse of 5 cm, but its area is   cm2,

which is not equivalent to 6 cm2.

49. OPEN ENDED  Draw a right triangle that has a hypotenuse of  units.

SOLUTION:  Use the Pythagorean Theorem to select two side lengths for a and b with the given value of c.

 

50. WRITING IN MATH  Explain how to determine whether segments in three lengths could form a right triangle.

SOLUTION:  

From the converse of the Pythagorean Theorem, if a2 + b

2 = c

2 then a, b, and c are the lengths of the side of a right

triangle. So, check to see whether the square of the greatest number is equal to the sum of the squares of the other two numbers. Consider triangle with sides of 9, 12 and 15 and a triangle with sides of 7, 13 and 19. 

   

51. GEOMETRY  Find the missing length.

A  −17

B  −

C  

D  17

SOLUTION:  

The correct choice is C.

52. What is a solution of this equation?

F  0, 3 G  3 H  0 J  no solutions

SOLUTION:  

The correct choice is H.

53. SHORT RESPONSE  A plumber charges $40 for the first hour of each house call plus $8 for each additional half hour. If the plumber works for 4 hours, how much does he charge?

SOLUTION:  Let x = the total number of hours worked.

The plumber charges $88 for 4 hours of work.

54. Find the next term in the geometric sequence .

A  

B  

C   

D  

SOLUTION:  

The correct choice is B.

Solve each equation. Check your solution.

55. 

SOLUTION:  

Check.

56. 

SOLUTION:  

Check.

57. 

SOLUTION:  

Check.

58. 

SOLUTION:  

Check.

59. 

SOLUTION:  

Check.

60. 

SOLUTION:  

Check.

There is no real solution.

Simplify each expression.

61. 

SOLUTION:  

62. 

SOLUTION:  

63. 

SOLUTION:  

64. 

SOLUTION:  

65. 

SOLUTION:  

66. 

SOLUTION:  

Describe how the graph of each function is related to the graph of f (x) = x2.

67. g(x) = x2 − 8

SOLUTION:  

The graph of f (x) = x2 + c represents a vertical translation of the parent graph. The value of c is –8, and –8 < 0. If c

< 0, the graph of f (x) = x2 is translated  units down. Therefore, the graph of g(x) = x

2 – 8 is a translation of the

parent graph shifted down 8 units.

68. h(x) = x2

SOLUTION:  

The graph of f (x) = ax2 stretches or compresses the graph of f (x) = x

2 vertically. The value of a is , and 0 <  <

1. If 0 <  < 1, the graph of f (x) = x2 is compressed vertically. Therefore, the graph of h(x) = x

2 is the parent

graph compressed vertically.

69. h(x) = −x2 + 5

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is 5, and 5 > 0. If c > 0, the graph of f (x) = x2 is translated

 units up. Therefore, the graph of h(x) = −x2 + 5 is a translation of the parent graph shifted up 8 units and

reflected across the x-axis.

70. g(x) = (x + 10)2

SOLUTION:  

The graph of f (x) = (x – c)2 represents a horizontal translation of the parent graph. The value of c is –10, and –10 <

0. If c < 0, the graph of f (x) = (x – c)2

is translated  units left. Therefore, the graph of g(x) = (x + 10)2 is a

translation of the parent graph shifted left 10 units.

71. g(x) = −2x2

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = ax

2 stretches or

compresses the graph of f (x) = x2 vertically. The value of a is –2, and |–2| > 1. If  > 1, the graph of f (x) = x

2 is

stretched vertically. Therefore, the graph of g(x) = –2x2 is the parent graph reflected across the x-axis and stretched

vertically.

72. h(x) = −x2 −

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is , and < 0. If c < 0, the graph of f (x) = x2 is

translated  units down. Therefore, the graph of h(x) = −x2 is a translation of the parent graph shifted down

 units and reflected across the x-axis.

73. ROCK CLIMBING  While rock climbing, Damaris launches a grappling hook from a height of 6 feet with an initialupward velocity of 56 feet per second. The hook just misses the stone ledge that she wants to scale. As it falls, the hook anchors on a ledge 30 feet above the ground. How long was the hook in the air?

SOLUTION:  

A half second after she throws the hook, it is 30 feet in the air. The hook continues up, then drops back down to the height of 30 feet 3 seconds after the throw. The hook was in the air for 3 seconds.

Find each product.74. (b + 8)(b + 2)

SOLUTION:  

75. (x − 4)(x − 9)

SOLUTION:  

76. (y + 4)(y − 8)

SOLUTION:  

77. (p + 2)(p − 10)

SOLUTION:  

78. (2w − 5)(w + 7)

SOLUTION:  

79. (8d + 3)(5d + 2)

SOLUTION:  

80. BUSINESS  The amount of money spent at West Outlet Mall continues to increase. The total T(x) in millions of

dollars can be estimated by the function T(x) = 12(1.12)x, where x is the number of years after it opened in 2005.

Find the amount of sales in 2015, 2016, and 2017.

SOLUTION:  

The sales for the mall in 2015 will be about $37.27 million; in 2016 will be about $41.74 million; and in 2017 will be about $46.75 million.

Solve each proportion.

81. 

SOLUTION:  

82. 

SOLUTION:  

83. 

SOLUTION:  

84. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 24

10-5 The Pythagorean Theorem

Page 25: Find each missing length. If necessary, round to the ......Find each missing length. If necessary, round to the nearest hundredth. 62/87,21 Use the Pythagorean Theorem, substituting

Find each missing length. If necessary, round to the nearest hundredth.

1. 

SOLUTION:  Use the Pythagorean Theorem, substituting 3 for a and 4 for b.

2. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 21 for c.

3. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for b and 19 for c.

4. 

SOLUTION:  Use the Pythagorean Theorem, substituting 8 for a and 12 for b.

5. BASEBALL  A baseball diamond is a square. The distance between consecutive bases is 90 feet.

a.  How far does a catcher have to throw the ball from home plate to second base? b.  How far does a third baseman throw the ball to the first baseman from a point in the baseline 15 feet from third to second base? c.  A base runner going from first to second base is 100 feet from home plate. How far is the runner from second base?

SOLUTION:  a. Use the Pythagorean Theorem, substituting 90 for a and 90 for b.

The catcher has to throw the ball about 127 ft from home plate to second base.   b. The diagram below illustrates the throw made by the third baseman.

The length of a is 90 – 15 or 75 feet. Find the length of the throw c by using the Pythagorean Theorem, substituting 75 for a and 90 for b.

The third baseman has to throw the ball about 117 feet to the first baseman.   c. The diagram below illustrates the position of the base runner.

Use the Pythagorean Theorem to find the length of side a by substituting 90 for b and 100 for c.

So, the base runner is about 44 feet from first base to second base. Therefore, the distance the base runner is from second is about 90 – 44 or 46 feet.  

Determine whether each set of measures can be the lengths of the sides of a right triangle.6. 8, 12, 16

SOLUTION:  

Since the measure of the longest side is 16, let c = 16, a = 8, and b = 12. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 8, 12, and 16 is not a right triangle.

7. 28, 45, 53

SOLUTION:  

Since the measure of the longest side is 53, let c = 53, a = 28, and b = 45. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 28, 45, and 53 is a right triangle.

8. 7, 24, 25

SOLUTION:  

Since the measure of the longest side is 25, let c = 25, a = 7, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 7, 24, and 25 is a right triangle.

9. 15, 25, 45

SOLUTION:  

Since the measure of the longest side is 45, let c = 45, a = 15, and b = 25. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 15, 25, and 45 is not a right triangle.

Find each missing length. If necessary, round to the nearest hundredth.

10. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for a and 14 for b.

11. 

SOLUTION:  Use the Pythagorean Theorem, substituting 2 for a and 12 for c.

12. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and 20 for b.

13. 

SOLUTION:  Use the Pythagorean Theorem, substituting 9 for b and 31 for c.

14. 

SOLUTION:  Use the Pythagorean Theorem, substituting 16 for a and 26 for c.

15. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and  for b.

16. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for b and 25 for c.

17. 

SOLUTION:  

Use the Pythagorean Theorem, substituting 5 for a and  for c.

18. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for b and  for c.

19. TELEVISION  Larry is buying an entertainment stand for his television. The diagonal of his television is 42 inches. The space for the television measures 30 inches by 36 inches. Will Larry’s television fit? Explain.

SOLUTION:  Use the Pythagorean Theorem, substituting 30 for a and 36 for b.

Yes; sample answer: The diagonal of the space in the TV stand is about 46.9 inches, which is greater than the diagonal of the television, so Larry’s TV will fit.

Determine whether each set of measures can be the lengths of the sides of a right triangle. Then determine whether they form a Pythagorean triple.

20. 9, 40, 41

SOLUTION:  

Since the measure of the longest side is 41, let c = 41, a = 9, and b = 40. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 9, 40, and 41 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

21. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = 3, and b = . Then determine whether c2 = a

2 +

b2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 3, , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

22. 

SOLUTION:  

Since the measure of the longest side is 12, let c = 12, a = 4, and b = . Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 4, , and 12 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

23. 

SOLUTION:  

Since the measure of the longest side is 14, let c = 14, a = , and b = 7. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths , 7, and 14 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

24. 8, 31.5, 32.5

SOLUTION:  

Since the measure of the longest side is 32.5, let c = 32.5, a = 8, and b = 31.5. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 8, 31.5, and 32.5 is a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number, but b and c are not whole numbers.

25. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = , and b = . Then determine whether c2 =

a2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths , , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

26. 18, 24, 30

SOLUTION:  

Since the measure of the longest side is 30, let c = 30, a = 18, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 18, 24, and 30 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

27. 36, 77, 85

SOLUTION:  

Since the measure of the longest side is 85, let c = 85, a = 36, and b = 77. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 36, 77, and 85 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

28. 17, 33, 98

SOLUTION:  Since the measure of the longest side is 98, let c = 98, a = 17, and b = 33. The length of c is greater than the sum of a and b, so this is not a triangle. 

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 17, 33, and 98 is not a triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

29. GEOMETRY  Refer to the triangle shown.

a.  What is a? b.  Find the area of the triangle.

SOLUTION:  a. Use the Pythagorean Theorem, substituting 11 for b and 23 for c.

b.

The area of the triangle is about 111.1 units2.

30. GARDENING  Khaliah wants to plant flowers in a triangular plot. She has three lengths of plastic garden edging that measure 8 feet, 15 feet, and 17 feet. Determine whether these pieces form a right triangle. Explain.

SOLUTION:  Yes; sample answer: The longest side is 17 feet so this has to be the hypotenuse.

82 + 15

2 = 17

2 so the pieces form a right triangle by the converse of the Pythagorean Theorem.

31. LADDER  Mr. Takeo is locked out of his house. The only open window is on the second floor. There is a bush along the edge of the house, so he places the neighbor’s ladder 10 feet from the house. To the nearest foot, what length of ladder does he need to reach the window?

SOLUTION:  Use the Pythagorean Theorem, substituting 10 for a and 28 for b.

He will need a 30-ft ladder to reach the window.

CCSS TOOLS  Find the length of the hypotenuse. Round to the nearest hundredth.

32. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for a and 10 for b.

33. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 7 for b.

34. DOLLHOUSE  Alonso is building a dollhouse for his sister’s birthday. The roof is 24 inches across and the slanted side is 16 inches long as shown. Find the height of the roof to the nearest tenth of an inch.

SOLUTION:  Use the Pythagorean Theorem, substituting 12 for b and 16 for c.

The height of the roof is 10.6 in.

35. GEOMETRY  Each side of a cube is 5 inches long. Find the length of a diagonal of the cube.

SOLUTION:  

Use the Pythagorean Theorem to find the diagonal of a side of the cube, substituting 5 for a and 5 for b.

Then, use the Pythagorean Theorem to find a diagonal of the cube, substituting 5 for a and  for b.

The length of a diagonal of the cube is about 8.66 in.

36. TOWN SQUARES  The largest town square in the world is Tiananmen Square in Beijing, China, covering 98 acres. a.  One square mile is 640 acres. Assuming that Tiananmen Square is a square, how many feet long is a side to the nearest foot? b.  To the nearest foot, what is the diagonal distance across Tiananmen Square?

SOLUTION:  a. First, use the conversion factor 1 square mile = 640 acres to convert the area of the square from acres to square miles.

So, 98 acres is 0.153125 square miles. Use dimensional analysis to convert this measure to square feet.  

  Next, use the formula for the area of a square to find the length of a side.

Therefore, a side of Tiananmen Square is about 2066 feet long.   b. Use the Pythagorean Theorem to find the length of the diagonal of the square, substituting 2066 for both a and b.

The diagonal distance across Tiananmen Square is about 2922 feet.

37. TRUCKS  Violeta needs to construct a ramp to roll a cart of moving boxes from her garage into the back of her truck. The truck is 6 feet from the garage. The back of the truck is 36 inches above the ground. How long does the ramp have to be?

SOLUTION:  First, rewrite 36 inches as 3 ft. Use the Pythagorean thereom, substituting 6 for a and 3 for b.

The ramp must be about 6.7 ft.

If c is the measure of the hypotenuse of a right triangle, find each missing measure. If necessary, round to the nearest hundredth.

38. a = x, b = x + 41, c = 85

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 36; b = 77

39. a = 8, b = x, c = x + 2

SOLUTION:  

b = 15; c = 17

40. a = 12, b = x − 2, c = x

SOLUTION:  

b = 35; c = 37

41. a = x, b = x + 7, c = 97

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 65; b = 72

42. a = x − 47, b = x, c = x + 2

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 16; b = 63; c = 65

43. a = x − 32, b = x − 1, c = x

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 9; b = 40; c = 41

44. GEOMETRY  A right triangle has one leg that is 8 inches shorter than the other leg. The hypotenuse is 30 inches long. Find the length of each leg.

SOLUTION:  

The length of each leg of the triangle is about 24.83 in. and about 16.83 in.

45. MULTIPLE REPRESENTATIONS In this problem, you will derive a method for finding the midpoint and length of a segment on the coordinate plane. a. Graphical Use a graph to find the lengths of the segments between (3, 2) and (8, 2) and between (4, 1) and (4, 9).Then find the midpoint of each segment. b. Logical Use what you learned in part a to write expressions for the lengths of the segments between (x1 , y) and

(x2 , y) and between (x, y1 ) and (x,  y2). What would be the midpoint of each segment?

c. Analytical Based on your results from part b, find the midpoint of the segment with endpoints at (x1, y1), and (x2,

y2).

d. Analytical Use the Pythagorean Theorem to write an expression for the distance between (x1, y1), and (x2, y2).

SOLUTION:  a.  From the graph, the length of the vertical segment is 9 – 1 or 8 units and the length of the horizontal line is 8 – 3 or 5 units.

The midpoints will be located in the middle of each segment, or the average of the coordinates. For the vertical segment, the value between 1 and 9 is 5, so the midpoint should be at (4, 5). For the horizontal segment, the value between 3 and 8 is 5.5, so the midpoint should be at (5.5, 2). b.  Distance: The length of the segment between (x1, y) and (x2, y) will be the absolute value of x1 – x2. The length

of the segment between (x, y1) and (x, y2) will be the absolute value of y1 – y2.

Midpoint: When the x-coordinates are identical, then the x-coordinate of the midpoint will also be the same value.

This is true for the y-coordinates as well. The midpoint of (x1, y) and (x2, y) is at the average of the x-coordinates

and y or at , and the midpoint of (x, y1) and (x, y2) is at .

c. When the x- and y-coordinates are both different, the midpoint should be at the average values of the coordinates,

or at .   d. Form a right triangle with the segment formed by the two points as the hypotenuse. Note that the other coordinateis (x2, y1) in the drawing. 

 

We know the Pythagorean Theorem is a2 + b

2 = c

2. We can solve this formula for c by taking the square root of

each side. So, . Now we can replace the variables with the lengths of each side. The length of

side a is x2 – x1. The length of side b is y2 – y1. The length of side c is now .

 

46. ERROR ANALYSIS  Wyatt and Dario are determining whether 36, 77, and 85 form a Pythagorean triple. Is eitherof them correct? Explain your reasoning.

SOLUTION:  Wyatt is correct. The square of the greatest value should be equal to the sum of the squares of the two smaller values.  Since this is the case, the numbers form a Pythagorean triple.

47. CCSS PERSEVERANCE  Find the value of x in the figure shown.

SOLUTION:  The figure can be separated into two right triangles. Let m represent the missing side length common to both right

triangles. From the Pythagorean Theorem, m2 = 2

2 + x

2 and 14

2 = 8

2 + m

2. Using substitution, you can find that 2

2 +

x2 = 14

2 – 8

2.

Solve for x.

48. REASONING  Provide a counterexample to the statement. Any two right triangles with the same hypotenuse have the same area.

SOLUTION:  Different lengths of a and b can produce the same value of c in the Pythagorean theorem.  

 

Sample answer: A right triangle with legs measuring 3 cm and 4 cm has a hypotenuse of 5 cm and an area of 6 cm2.

A right triangle with legs measuring 2 cm and  cm also has a hypotenuse of 5 cm, but its area is   cm2,

which is not equivalent to 6 cm2.

49. OPEN ENDED  Draw a right triangle that has a hypotenuse of  units.

SOLUTION:  Use the Pythagorean Theorem to select two side lengths for a and b with the given value of c.

 

50. WRITING IN MATH  Explain how to determine whether segments in three lengths could form a right triangle.

SOLUTION:  

From the converse of the Pythagorean Theorem, if a2 + b

2 = c

2 then a, b, and c are the lengths of the side of a right

triangle. So, check to see whether the square of the greatest number is equal to the sum of the squares of the other two numbers. Consider triangle with sides of 9, 12 and 15 and a triangle with sides of 7, 13 and 19. 

   

51. GEOMETRY  Find the missing length.

A  −17

B  −

C  

D  17

SOLUTION:  

The correct choice is C.

52. What is a solution of this equation?

F  0, 3 G  3 H  0 J  no solutions

SOLUTION:  

The correct choice is H.

53. SHORT RESPONSE  A plumber charges $40 for the first hour of each house call plus $8 for each additional half hour. If the plumber works for 4 hours, how much does he charge?

SOLUTION:  Let x = the total number of hours worked.

The plumber charges $88 for 4 hours of work.

54. Find the next term in the geometric sequence .

A  

B  

C   

D  

SOLUTION:  

The correct choice is B.

Solve each equation. Check your solution.

55. 

SOLUTION:  

Check.

56. 

SOLUTION:  

Check.

57. 

SOLUTION:  

Check.

58. 

SOLUTION:  

Check.

59. 

SOLUTION:  

Check.

60. 

SOLUTION:  

Check.

There is no real solution.

Simplify each expression.

61. 

SOLUTION:  

62. 

SOLUTION:  

63. 

SOLUTION:  

64. 

SOLUTION:  

65. 

SOLUTION:  

66. 

SOLUTION:  

Describe how the graph of each function is related to the graph of f (x) = x2.

67. g(x) = x2 − 8

SOLUTION:  

The graph of f (x) = x2 + c represents a vertical translation of the parent graph. The value of c is –8, and –8 < 0. If c

< 0, the graph of f (x) = x2 is translated  units down. Therefore, the graph of g(x) = x

2 – 8 is a translation of the

parent graph shifted down 8 units.

68. h(x) = x2

SOLUTION:  

The graph of f (x) = ax2 stretches or compresses the graph of f (x) = x

2 vertically. The value of a is , and 0 <  <

1. If 0 <  < 1, the graph of f (x) = x2 is compressed vertically. Therefore, the graph of h(x) = x

2 is the parent

graph compressed vertically.

69. h(x) = −x2 + 5

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is 5, and 5 > 0. If c > 0, the graph of f (x) = x2 is translated

 units up. Therefore, the graph of h(x) = −x2 + 5 is a translation of the parent graph shifted up 8 units and

reflected across the x-axis.

70. g(x) = (x + 10)2

SOLUTION:  

The graph of f (x) = (x – c)2 represents a horizontal translation of the parent graph. The value of c is –10, and –10 <

0. If c < 0, the graph of f (x) = (x – c)2

is translated  units left. Therefore, the graph of g(x) = (x + 10)2 is a

translation of the parent graph shifted left 10 units.

71. g(x) = −2x2

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = ax

2 stretches or

compresses the graph of f (x) = x2 vertically. The value of a is –2, and |–2| > 1. If  > 1, the graph of f (x) = x

2 is

stretched vertically. Therefore, the graph of g(x) = –2x2 is the parent graph reflected across the x-axis and stretched

vertically.

72. h(x) = −x2 −

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is , and < 0. If c < 0, the graph of f (x) = x2 is

translated  units down. Therefore, the graph of h(x) = −x2 is a translation of the parent graph shifted down

 units and reflected across the x-axis.

73. ROCK CLIMBING  While rock climbing, Damaris launches a grappling hook from a height of 6 feet with an initialupward velocity of 56 feet per second. The hook just misses the stone ledge that she wants to scale. As it falls, the hook anchors on a ledge 30 feet above the ground. How long was the hook in the air?

SOLUTION:  

A half second after she throws the hook, it is 30 feet in the air. The hook continues up, then drops back down to the height of 30 feet 3 seconds after the throw. The hook was in the air for 3 seconds.

Find each product.74. (b + 8)(b + 2)

SOLUTION:  

75. (x − 4)(x − 9)

SOLUTION:  

76. (y + 4)(y − 8)

SOLUTION:  

77. (p + 2)(p − 10)

SOLUTION:  

78. (2w − 5)(w + 7)

SOLUTION:  

79. (8d + 3)(5d + 2)

SOLUTION:  

80. BUSINESS  The amount of money spent at West Outlet Mall continues to increase. The total T(x) in millions of

dollars can be estimated by the function T(x) = 12(1.12)x, where x is the number of years after it opened in 2005.

Find the amount of sales in 2015, 2016, and 2017.

SOLUTION:  

The sales for the mall in 2015 will be about $37.27 million; in 2016 will be about $41.74 million; and in 2017 will be about $46.75 million.

Solve each proportion.

81. 

SOLUTION:  

82. 

SOLUTION:  

83. 

SOLUTION:  

84. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 25

10-5 The Pythagorean Theorem

Page 26: Find each missing length. If necessary, round to the ......Find each missing length. If necessary, round to the nearest hundredth. 62/87,21 Use the Pythagorean Theorem, substituting

Find each missing length. If necessary, round to the nearest hundredth.

1. 

SOLUTION:  Use the Pythagorean Theorem, substituting 3 for a and 4 for b.

2. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 21 for c.

3. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for b and 19 for c.

4. 

SOLUTION:  Use the Pythagorean Theorem, substituting 8 for a and 12 for b.

5. BASEBALL  A baseball diamond is a square. The distance between consecutive bases is 90 feet.

a.  How far does a catcher have to throw the ball from home plate to second base? b.  How far does a third baseman throw the ball to the first baseman from a point in the baseline 15 feet from third to second base? c.  A base runner going from first to second base is 100 feet from home plate. How far is the runner from second base?

SOLUTION:  a. Use the Pythagorean Theorem, substituting 90 for a and 90 for b.

The catcher has to throw the ball about 127 ft from home plate to second base.   b. The diagram below illustrates the throw made by the third baseman.

The length of a is 90 – 15 or 75 feet. Find the length of the throw c by using the Pythagorean Theorem, substituting 75 for a and 90 for b.

The third baseman has to throw the ball about 117 feet to the first baseman.   c. The diagram below illustrates the position of the base runner.

Use the Pythagorean Theorem to find the length of side a by substituting 90 for b and 100 for c.

So, the base runner is about 44 feet from first base to second base. Therefore, the distance the base runner is from second is about 90 – 44 or 46 feet.  

Determine whether each set of measures can be the lengths of the sides of a right triangle.6. 8, 12, 16

SOLUTION:  

Since the measure of the longest side is 16, let c = 16, a = 8, and b = 12. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 8, 12, and 16 is not a right triangle.

7. 28, 45, 53

SOLUTION:  

Since the measure of the longest side is 53, let c = 53, a = 28, and b = 45. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 28, 45, and 53 is a right triangle.

8. 7, 24, 25

SOLUTION:  

Since the measure of the longest side is 25, let c = 25, a = 7, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 7, 24, and 25 is a right triangle.

9. 15, 25, 45

SOLUTION:  

Since the measure of the longest side is 45, let c = 45, a = 15, and b = 25. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 15, 25, and 45 is not a right triangle.

Find each missing length. If necessary, round to the nearest hundredth.

10. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for a and 14 for b.

11. 

SOLUTION:  Use the Pythagorean Theorem, substituting 2 for a and 12 for c.

12. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and 20 for b.

13. 

SOLUTION:  Use the Pythagorean Theorem, substituting 9 for b and 31 for c.

14. 

SOLUTION:  Use the Pythagorean Theorem, substituting 16 for a and 26 for c.

15. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and  for b.

16. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for b and 25 for c.

17. 

SOLUTION:  

Use the Pythagorean Theorem, substituting 5 for a and  for c.

18. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for b and  for c.

19. TELEVISION  Larry is buying an entertainment stand for his television. The diagonal of his television is 42 inches. The space for the television measures 30 inches by 36 inches. Will Larry’s television fit? Explain.

SOLUTION:  Use the Pythagorean Theorem, substituting 30 for a and 36 for b.

Yes; sample answer: The diagonal of the space in the TV stand is about 46.9 inches, which is greater than the diagonal of the television, so Larry’s TV will fit.

Determine whether each set of measures can be the lengths of the sides of a right triangle. Then determine whether they form a Pythagorean triple.

20. 9, 40, 41

SOLUTION:  

Since the measure of the longest side is 41, let c = 41, a = 9, and b = 40. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 9, 40, and 41 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

21. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = 3, and b = . Then determine whether c2 = a

2 +

b2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 3, , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

22. 

SOLUTION:  

Since the measure of the longest side is 12, let c = 12, a = 4, and b = . Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 4, , and 12 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

23. 

SOLUTION:  

Since the measure of the longest side is 14, let c = 14, a = , and b = 7. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths , 7, and 14 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

24. 8, 31.5, 32.5

SOLUTION:  

Since the measure of the longest side is 32.5, let c = 32.5, a = 8, and b = 31.5. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 8, 31.5, and 32.5 is a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number, but b and c are not whole numbers.

25. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = , and b = . Then determine whether c2 =

a2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths , , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

26. 18, 24, 30

SOLUTION:  

Since the measure of the longest side is 30, let c = 30, a = 18, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 18, 24, and 30 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

27. 36, 77, 85

SOLUTION:  

Since the measure of the longest side is 85, let c = 85, a = 36, and b = 77. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 36, 77, and 85 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

28. 17, 33, 98

SOLUTION:  Since the measure of the longest side is 98, let c = 98, a = 17, and b = 33. The length of c is greater than the sum of a and b, so this is not a triangle. 

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 17, 33, and 98 is not a triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

29. GEOMETRY  Refer to the triangle shown.

a.  What is a? b.  Find the area of the triangle.

SOLUTION:  a. Use the Pythagorean Theorem, substituting 11 for b and 23 for c.

b.

The area of the triangle is about 111.1 units2.

30. GARDENING  Khaliah wants to plant flowers in a triangular plot. She has three lengths of plastic garden edging that measure 8 feet, 15 feet, and 17 feet. Determine whether these pieces form a right triangle. Explain.

SOLUTION:  Yes; sample answer: The longest side is 17 feet so this has to be the hypotenuse.

82 + 15

2 = 17

2 so the pieces form a right triangle by the converse of the Pythagorean Theorem.

31. LADDER  Mr. Takeo is locked out of his house. The only open window is on the second floor. There is a bush along the edge of the house, so he places the neighbor’s ladder 10 feet from the house. To the nearest foot, what length of ladder does he need to reach the window?

SOLUTION:  Use the Pythagorean Theorem, substituting 10 for a and 28 for b.

He will need a 30-ft ladder to reach the window.

CCSS TOOLS  Find the length of the hypotenuse. Round to the nearest hundredth.

32. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for a and 10 for b.

33. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 7 for b.

34. DOLLHOUSE  Alonso is building a dollhouse for his sister’s birthday. The roof is 24 inches across and the slanted side is 16 inches long as shown. Find the height of the roof to the nearest tenth of an inch.

SOLUTION:  Use the Pythagorean Theorem, substituting 12 for b and 16 for c.

The height of the roof is 10.6 in.

35. GEOMETRY  Each side of a cube is 5 inches long. Find the length of a diagonal of the cube.

SOLUTION:  

Use the Pythagorean Theorem to find the diagonal of a side of the cube, substituting 5 for a and 5 for b.

Then, use the Pythagorean Theorem to find a diagonal of the cube, substituting 5 for a and  for b.

The length of a diagonal of the cube is about 8.66 in.

36. TOWN SQUARES  The largest town square in the world is Tiananmen Square in Beijing, China, covering 98 acres. a.  One square mile is 640 acres. Assuming that Tiananmen Square is a square, how many feet long is a side to the nearest foot? b.  To the nearest foot, what is the diagonal distance across Tiananmen Square?

SOLUTION:  a. First, use the conversion factor 1 square mile = 640 acres to convert the area of the square from acres to square miles.

So, 98 acres is 0.153125 square miles. Use dimensional analysis to convert this measure to square feet.  

  Next, use the formula for the area of a square to find the length of a side.

Therefore, a side of Tiananmen Square is about 2066 feet long.   b. Use the Pythagorean Theorem to find the length of the diagonal of the square, substituting 2066 for both a and b.

The diagonal distance across Tiananmen Square is about 2922 feet.

37. TRUCKS  Violeta needs to construct a ramp to roll a cart of moving boxes from her garage into the back of her truck. The truck is 6 feet from the garage. The back of the truck is 36 inches above the ground. How long does the ramp have to be?

SOLUTION:  First, rewrite 36 inches as 3 ft. Use the Pythagorean thereom, substituting 6 for a and 3 for b.

The ramp must be about 6.7 ft.

If c is the measure of the hypotenuse of a right triangle, find each missing measure. If necessary, round to the nearest hundredth.

38. a = x, b = x + 41, c = 85

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 36; b = 77

39. a = 8, b = x, c = x + 2

SOLUTION:  

b = 15; c = 17

40. a = 12, b = x − 2, c = x

SOLUTION:  

b = 35; c = 37

41. a = x, b = x + 7, c = 97

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 65; b = 72

42. a = x − 47, b = x, c = x + 2

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 16; b = 63; c = 65

43. a = x − 32, b = x − 1, c = x

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 9; b = 40; c = 41

44. GEOMETRY  A right triangle has one leg that is 8 inches shorter than the other leg. The hypotenuse is 30 inches long. Find the length of each leg.

SOLUTION:  

The length of each leg of the triangle is about 24.83 in. and about 16.83 in.

45. MULTIPLE REPRESENTATIONS In this problem, you will derive a method for finding the midpoint and length of a segment on the coordinate plane. a. Graphical Use a graph to find the lengths of the segments between (3, 2) and (8, 2) and between (4, 1) and (4, 9).Then find the midpoint of each segment. b. Logical Use what you learned in part a to write expressions for the lengths of the segments between (x1 , y) and

(x2 , y) and between (x, y1 ) and (x,  y2). What would be the midpoint of each segment?

c. Analytical Based on your results from part b, find the midpoint of the segment with endpoints at (x1, y1), and (x2,

y2).

d. Analytical Use the Pythagorean Theorem to write an expression for the distance between (x1, y1), and (x2, y2).

SOLUTION:  a.  From the graph, the length of the vertical segment is 9 – 1 or 8 units and the length of the horizontal line is 8 – 3 or 5 units.

The midpoints will be located in the middle of each segment, or the average of the coordinates. For the vertical segment, the value between 1 and 9 is 5, so the midpoint should be at (4, 5). For the horizontal segment, the value between 3 and 8 is 5.5, so the midpoint should be at (5.5, 2). b.  Distance: The length of the segment between (x1, y) and (x2, y) will be the absolute value of x1 – x2. The length

of the segment between (x, y1) and (x, y2) will be the absolute value of y1 – y2.

Midpoint: When the x-coordinates are identical, then the x-coordinate of the midpoint will also be the same value.

This is true for the y-coordinates as well. The midpoint of (x1, y) and (x2, y) is at the average of the x-coordinates

and y or at , and the midpoint of (x, y1) and (x, y2) is at .

c. When the x- and y-coordinates are both different, the midpoint should be at the average values of the coordinates,

or at .   d. Form a right triangle with the segment formed by the two points as the hypotenuse. Note that the other coordinateis (x2, y1) in the drawing. 

 

We know the Pythagorean Theorem is a2 + b

2 = c

2. We can solve this formula for c by taking the square root of

each side. So, . Now we can replace the variables with the lengths of each side. The length of

side a is x2 – x1. The length of side b is y2 – y1. The length of side c is now .

 

46. ERROR ANALYSIS  Wyatt and Dario are determining whether 36, 77, and 85 form a Pythagorean triple. Is eitherof them correct? Explain your reasoning.

SOLUTION:  Wyatt is correct. The square of the greatest value should be equal to the sum of the squares of the two smaller values.  Since this is the case, the numbers form a Pythagorean triple.

47. CCSS PERSEVERANCE  Find the value of x in the figure shown.

SOLUTION:  The figure can be separated into two right triangles. Let m represent the missing side length common to both right

triangles. From the Pythagorean Theorem, m2 = 2

2 + x

2 and 14

2 = 8

2 + m

2. Using substitution, you can find that 2

2 +

x2 = 14

2 – 8

2.

Solve for x.

48. REASONING  Provide a counterexample to the statement. Any two right triangles with the same hypotenuse have the same area.

SOLUTION:  Different lengths of a and b can produce the same value of c in the Pythagorean theorem.  

 

Sample answer: A right triangle with legs measuring 3 cm and 4 cm has a hypotenuse of 5 cm and an area of 6 cm2.

A right triangle with legs measuring 2 cm and  cm also has a hypotenuse of 5 cm, but its area is   cm2,

which is not equivalent to 6 cm2.

49. OPEN ENDED  Draw a right triangle that has a hypotenuse of  units.

SOLUTION:  Use the Pythagorean Theorem to select two side lengths for a and b with the given value of c.

 

50. WRITING IN MATH  Explain how to determine whether segments in three lengths could form a right triangle.

SOLUTION:  

From the converse of the Pythagorean Theorem, if a2 + b

2 = c

2 then a, b, and c are the lengths of the side of a right

triangle. So, check to see whether the square of the greatest number is equal to the sum of the squares of the other two numbers. Consider triangle with sides of 9, 12 and 15 and a triangle with sides of 7, 13 and 19. 

   

51. GEOMETRY  Find the missing length.

A  −17

B  −

C  

D  17

SOLUTION:  

The correct choice is C.

52. What is a solution of this equation?

F  0, 3 G  3 H  0 J  no solutions

SOLUTION:  

The correct choice is H.

53. SHORT RESPONSE  A plumber charges $40 for the first hour of each house call plus $8 for each additional half hour. If the plumber works for 4 hours, how much does he charge?

SOLUTION:  Let x = the total number of hours worked.

The plumber charges $88 for 4 hours of work.

54. Find the next term in the geometric sequence .

A  

B  

C   

D  

SOLUTION:  

The correct choice is B.

Solve each equation. Check your solution.

55. 

SOLUTION:  

Check.

56. 

SOLUTION:  

Check.

57. 

SOLUTION:  

Check.

58. 

SOLUTION:  

Check.

59. 

SOLUTION:  

Check.

60. 

SOLUTION:  

Check.

There is no real solution.

Simplify each expression.

61. 

SOLUTION:  

62. 

SOLUTION:  

63. 

SOLUTION:  

64. 

SOLUTION:  

65. 

SOLUTION:  

66. 

SOLUTION:  

Describe how the graph of each function is related to the graph of f (x) = x2.

67. g(x) = x2 − 8

SOLUTION:  

The graph of f (x) = x2 + c represents a vertical translation of the parent graph. The value of c is –8, and –8 < 0. If c

< 0, the graph of f (x) = x2 is translated  units down. Therefore, the graph of g(x) = x

2 – 8 is a translation of the

parent graph shifted down 8 units.

68. h(x) = x2

SOLUTION:  

The graph of f (x) = ax2 stretches or compresses the graph of f (x) = x

2 vertically. The value of a is , and 0 <  <

1. If 0 <  < 1, the graph of f (x) = x2 is compressed vertically. Therefore, the graph of h(x) = x

2 is the parent

graph compressed vertically.

69. h(x) = −x2 + 5

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is 5, and 5 > 0. If c > 0, the graph of f (x) = x2 is translated

 units up. Therefore, the graph of h(x) = −x2 + 5 is a translation of the parent graph shifted up 8 units and

reflected across the x-axis.

70. g(x) = (x + 10)2

SOLUTION:  

The graph of f (x) = (x – c)2 represents a horizontal translation of the parent graph. The value of c is –10, and –10 <

0. If c < 0, the graph of f (x) = (x – c)2

is translated  units left. Therefore, the graph of g(x) = (x + 10)2 is a

translation of the parent graph shifted left 10 units.

71. g(x) = −2x2

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = ax

2 stretches or

compresses the graph of f (x) = x2 vertically. The value of a is –2, and |–2| > 1. If  > 1, the graph of f (x) = x

2 is

stretched vertically. Therefore, the graph of g(x) = –2x2 is the parent graph reflected across the x-axis and stretched

vertically.

72. h(x) = −x2 −

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is , and < 0. If c < 0, the graph of f (x) = x2 is

translated  units down. Therefore, the graph of h(x) = −x2 is a translation of the parent graph shifted down

 units and reflected across the x-axis.

73. ROCK CLIMBING  While rock climbing, Damaris launches a grappling hook from a height of 6 feet with an initialupward velocity of 56 feet per second. The hook just misses the stone ledge that she wants to scale. As it falls, the hook anchors on a ledge 30 feet above the ground. How long was the hook in the air?

SOLUTION:  

A half second after she throws the hook, it is 30 feet in the air. The hook continues up, then drops back down to the height of 30 feet 3 seconds after the throw. The hook was in the air for 3 seconds.

Find each product.74. (b + 8)(b + 2)

SOLUTION:  

75. (x − 4)(x − 9)

SOLUTION:  

76. (y + 4)(y − 8)

SOLUTION:  

77. (p + 2)(p − 10)

SOLUTION:  

78. (2w − 5)(w + 7)

SOLUTION:  

79. (8d + 3)(5d + 2)

SOLUTION:  

80. BUSINESS  The amount of money spent at West Outlet Mall continues to increase. The total T(x) in millions of

dollars can be estimated by the function T(x) = 12(1.12)x, where x is the number of years after it opened in 2005.

Find the amount of sales in 2015, 2016, and 2017.

SOLUTION:  

The sales for the mall in 2015 will be about $37.27 million; in 2016 will be about $41.74 million; and in 2017 will be about $46.75 million.

Solve each proportion.

81. 

SOLUTION:  

82. 

SOLUTION:  

83. 

SOLUTION:  

84. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 26

10-5 The Pythagorean Theorem

Page 27: Find each missing length. If necessary, round to the ......Find each missing length. If necessary, round to the nearest hundredth. 62/87,21 Use the Pythagorean Theorem, substituting

Find each missing length. If necessary, round to the nearest hundredth.

1. 

SOLUTION:  Use the Pythagorean Theorem, substituting 3 for a and 4 for b.

2. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 21 for c.

3. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for b and 19 for c.

4. 

SOLUTION:  Use the Pythagorean Theorem, substituting 8 for a and 12 for b.

5. BASEBALL  A baseball diamond is a square. The distance between consecutive bases is 90 feet.

a.  How far does a catcher have to throw the ball from home plate to second base? b.  How far does a third baseman throw the ball to the first baseman from a point in the baseline 15 feet from third to second base? c.  A base runner going from first to second base is 100 feet from home plate. How far is the runner from second base?

SOLUTION:  a. Use the Pythagorean Theorem, substituting 90 for a and 90 for b.

The catcher has to throw the ball about 127 ft from home plate to second base.   b. The diagram below illustrates the throw made by the third baseman.

The length of a is 90 – 15 or 75 feet. Find the length of the throw c by using the Pythagorean Theorem, substituting 75 for a and 90 for b.

The third baseman has to throw the ball about 117 feet to the first baseman.   c. The diagram below illustrates the position of the base runner.

Use the Pythagorean Theorem to find the length of side a by substituting 90 for b and 100 for c.

So, the base runner is about 44 feet from first base to second base. Therefore, the distance the base runner is from second is about 90 – 44 or 46 feet.  

Determine whether each set of measures can be the lengths of the sides of a right triangle.6. 8, 12, 16

SOLUTION:  

Since the measure of the longest side is 16, let c = 16, a = 8, and b = 12. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 8, 12, and 16 is not a right triangle.

7. 28, 45, 53

SOLUTION:  

Since the measure of the longest side is 53, let c = 53, a = 28, and b = 45. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 28, 45, and 53 is a right triangle.

8. 7, 24, 25

SOLUTION:  

Since the measure of the longest side is 25, let c = 25, a = 7, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 7, 24, and 25 is a right triangle.

9. 15, 25, 45

SOLUTION:  

Since the measure of the longest side is 45, let c = 45, a = 15, and b = 25. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 15, 25, and 45 is not a right triangle.

Find each missing length. If necessary, round to the nearest hundredth.

10. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for a and 14 for b.

11. 

SOLUTION:  Use the Pythagorean Theorem, substituting 2 for a and 12 for c.

12. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and 20 for b.

13. 

SOLUTION:  Use the Pythagorean Theorem, substituting 9 for b and 31 for c.

14. 

SOLUTION:  Use the Pythagorean Theorem, substituting 16 for a and 26 for c.

15. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and  for b.

16. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for b and 25 for c.

17. 

SOLUTION:  

Use the Pythagorean Theorem, substituting 5 for a and  for c.

18. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for b and  for c.

19. TELEVISION  Larry is buying an entertainment stand for his television. The diagonal of his television is 42 inches. The space for the television measures 30 inches by 36 inches. Will Larry’s television fit? Explain.

SOLUTION:  Use the Pythagorean Theorem, substituting 30 for a and 36 for b.

Yes; sample answer: The diagonal of the space in the TV stand is about 46.9 inches, which is greater than the diagonal of the television, so Larry’s TV will fit.

Determine whether each set of measures can be the lengths of the sides of a right triangle. Then determine whether they form a Pythagorean triple.

20. 9, 40, 41

SOLUTION:  

Since the measure of the longest side is 41, let c = 41, a = 9, and b = 40. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 9, 40, and 41 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

21. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = 3, and b = . Then determine whether c2 = a

2 +

b2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 3, , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

22. 

SOLUTION:  

Since the measure of the longest side is 12, let c = 12, a = 4, and b = . Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 4, , and 12 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

23. 

SOLUTION:  

Since the measure of the longest side is 14, let c = 14, a = , and b = 7. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths , 7, and 14 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

24. 8, 31.5, 32.5

SOLUTION:  

Since the measure of the longest side is 32.5, let c = 32.5, a = 8, and b = 31.5. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 8, 31.5, and 32.5 is a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number, but b and c are not whole numbers.

25. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = , and b = . Then determine whether c2 =

a2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths , , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

26. 18, 24, 30

SOLUTION:  

Since the measure of the longest side is 30, let c = 30, a = 18, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 18, 24, and 30 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

27. 36, 77, 85

SOLUTION:  

Since the measure of the longest side is 85, let c = 85, a = 36, and b = 77. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 36, 77, and 85 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

28. 17, 33, 98

SOLUTION:  Since the measure of the longest side is 98, let c = 98, a = 17, and b = 33. The length of c is greater than the sum of a and b, so this is not a triangle. 

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 17, 33, and 98 is not a triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

29. GEOMETRY  Refer to the triangle shown.

a.  What is a? b.  Find the area of the triangle.

SOLUTION:  a. Use the Pythagorean Theorem, substituting 11 for b and 23 for c.

b.

The area of the triangle is about 111.1 units2.

30. GARDENING  Khaliah wants to plant flowers in a triangular plot. She has three lengths of plastic garden edging that measure 8 feet, 15 feet, and 17 feet. Determine whether these pieces form a right triangle. Explain.

SOLUTION:  Yes; sample answer: The longest side is 17 feet so this has to be the hypotenuse.

82 + 15

2 = 17

2 so the pieces form a right triangle by the converse of the Pythagorean Theorem.

31. LADDER  Mr. Takeo is locked out of his house. The only open window is on the second floor. There is a bush along the edge of the house, so he places the neighbor’s ladder 10 feet from the house. To the nearest foot, what length of ladder does he need to reach the window?

SOLUTION:  Use the Pythagorean Theorem, substituting 10 for a and 28 for b.

He will need a 30-ft ladder to reach the window.

CCSS TOOLS  Find the length of the hypotenuse. Round to the nearest hundredth.

32. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for a and 10 for b.

33. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 7 for b.

34. DOLLHOUSE  Alonso is building a dollhouse for his sister’s birthday. The roof is 24 inches across and the slanted side is 16 inches long as shown. Find the height of the roof to the nearest tenth of an inch.

SOLUTION:  Use the Pythagorean Theorem, substituting 12 for b and 16 for c.

The height of the roof is 10.6 in.

35. GEOMETRY  Each side of a cube is 5 inches long. Find the length of a diagonal of the cube.

SOLUTION:  

Use the Pythagorean Theorem to find the diagonal of a side of the cube, substituting 5 for a and 5 for b.

Then, use the Pythagorean Theorem to find a diagonal of the cube, substituting 5 for a and  for b.

The length of a diagonal of the cube is about 8.66 in.

36. TOWN SQUARES  The largest town square in the world is Tiananmen Square in Beijing, China, covering 98 acres. a.  One square mile is 640 acres. Assuming that Tiananmen Square is a square, how many feet long is a side to the nearest foot? b.  To the nearest foot, what is the diagonal distance across Tiananmen Square?

SOLUTION:  a. First, use the conversion factor 1 square mile = 640 acres to convert the area of the square from acres to square miles.

So, 98 acres is 0.153125 square miles. Use dimensional analysis to convert this measure to square feet.  

  Next, use the formula for the area of a square to find the length of a side.

Therefore, a side of Tiananmen Square is about 2066 feet long.   b. Use the Pythagorean Theorem to find the length of the diagonal of the square, substituting 2066 for both a and b.

The diagonal distance across Tiananmen Square is about 2922 feet.

37. TRUCKS  Violeta needs to construct a ramp to roll a cart of moving boxes from her garage into the back of her truck. The truck is 6 feet from the garage. The back of the truck is 36 inches above the ground. How long does the ramp have to be?

SOLUTION:  First, rewrite 36 inches as 3 ft. Use the Pythagorean thereom, substituting 6 for a and 3 for b.

The ramp must be about 6.7 ft.

If c is the measure of the hypotenuse of a right triangle, find each missing measure. If necessary, round to the nearest hundredth.

38. a = x, b = x + 41, c = 85

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 36; b = 77

39. a = 8, b = x, c = x + 2

SOLUTION:  

b = 15; c = 17

40. a = 12, b = x − 2, c = x

SOLUTION:  

b = 35; c = 37

41. a = x, b = x + 7, c = 97

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 65; b = 72

42. a = x − 47, b = x, c = x + 2

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 16; b = 63; c = 65

43. a = x − 32, b = x − 1, c = x

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 9; b = 40; c = 41

44. GEOMETRY  A right triangle has one leg that is 8 inches shorter than the other leg. The hypotenuse is 30 inches long. Find the length of each leg.

SOLUTION:  

The length of each leg of the triangle is about 24.83 in. and about 16.83 in.

45. MULTIPLE REPRESENTATIONS In this problem, you will derive a method for finding the midpoint and length of a segment on the coordinate plane. a. Graphical Use a graph to find the lengths of the segments between (3, 2) and (8, 2) and between (4, 1) and (4, 9).Then find the midpoint of each segment. b. Logical Use what you learned in part a to write expressions for the lengths of the segments between (x1 , y) and

(x2 , y) and between (x, y1 ) and (x,  y2). What would be the midpoint of each segment?

c. Analytical Based on your results from part b, find the midpoint of the segment with endpoints at (x1, y1), and (x2,

y2).

d. Analytical Use the Pythagorean Theorem to write an expression for the distance between (x1, y1), and (x2, y2).

SOLUTION:  a.  From the graph, the length of the vertical segment is 9 – 1 or 8 units and the length of the horizontal line is 8 – 3 or 5 units.

The midpoints will be located in the middle of each segment, or the average of the coordinates. For the vertical segment, the value between 1 and 9 is 5, so the midpoint should be at (4, 5). For the horizontal segment, the value between 3 and 8 is 5.5, so the midpoint should be at (5.5, 2). b.  Distance: The length of the segment between (x1, y) and (x2, y) will be the absolute value of x1 – x2. The length

of the segment between (x, y1) and (x, y2) will be the absolute value of y1 – y2.

Midpoint: When the x-coordinates are identical, then the x-coordinate of the midpoint will also be the same value.

This is true for the y-coordinates as well. The midpoint of (x1, y) and (x2, y) is at the average of the x-coordinates

and y or at , and the midpoint of (x, y1) and (x, y2) is at .

c. When the x- and y-coordinates are both different, the midpoint should be at the average values of the coordinates,

or at .   d. Form a right triangle with the segment formed by the two points as the hypotenuse. Note that the other coordinateis (x2, y1) in the drawing. 

 

We know the Pythagorean Theorem is a2 + b

2 = c

2. We can solve this formula for c by taking the square root of

each side. So, . Now we can replace the variables with the lengths of each side. The length of

side a is x2 – x1. The length of side b is y2 – y1. The length of side c is now .

 

46. ERROR ANALYSIS  Wyatt and Dario are determining whether 36, 77, and 85 form a Pythagorean triple. Is eitherof them correct? Explain your reasoning.

SOLUTION:  Wyatt is correct. The square of the greatest value should be equal to the sum of the squares of the two smaller values.  Since this is the case, the numbers form a Pythagorean triple.

47. CCSS PERSEVERANCE  Find the value of x in the figure shown.

SOLUTION:  The figure can be separated into two right triangles. Let m represent the missing side length common to both right

triangles. From the Pythagorean Theorem, m2 = 2

2 + x

2 and 14

2 = 8

2 + m

2. Using substitution, you can find that 2

2 +

x2 = 14

2 – 8

2.

Solve for x.

48. REASONING  Provide a counterexample to the statement. Any two right triangles with the same hypotenuse have the same area.

SOLUTION:  Different lengths of a and b can produce the same value of c in the Pythagorean theorem.  

 

Sample answer: A right triangle with legs measuring 3 cm and 4 cm has a hypotenuse of 5 cm and an area of 6 cm2.

A right triangle with legs measuring 2 cm and  cm also has a hypotenuse of 5 cm, but its area is   cm2,

which is not equivalent to 6 cm2.

49. OPEN ENDED  Draw a right triangle that has a hypotenuse of  units.

SOLUTION:  Use the Pythagorean Theorem to select two side lengths for a and b with the given value of c.

 

50. WRITING IN MATH  Explain how to determine whether segments in three lengths could form a right triangle.

SOLUTION:  

From the converse of the Pythagorean Theorem, if a2 + b

2 = c

2 then a, b, and c are the lengths of the side of a right

triangle. So, check to see whether the square of the greatest number is equal to the sum of the squares of the other two numbers. Consider triangle with sides of 9, 12 and 15 and a triangle with sides of 7, 13 and 19. 

   

51. GEOMETRY  Find the missing length.

A  −17

B  −

C  

D  17

SOLUTION:  

The correct choice is C.

52. What is a solution of this equation?

F  0, 3 G  3 H  0 J  no solutions

SOLUTION:  

The correct choice is H.

53. SHORT RESPONSE  A plumber charges $40 for the first hour of each house call plus $8 for each additional half hour. If the plumber works for 4 hours, how much does he charge?

SOLUTION:  Let x = the total number of hours worked.

The plumber charges $88 for 4 hours of work.

54. Find the next term in the geometric sequence .

A  

B  

C   

D  

SOLUTION:  

The correct choice is B.

Solve each equation. Check your solution.

55. 

SOLUTION:  

Check.

56. 

SOLUTION:  

Check.

57. 

SOLUTION:  

Check.

58. 

SOLUTION:  

Check.

59. 

SOLUTION:  

Check.

60. 

SOLUTION:  

Check.

There is no real solution.

Simplify each expression.

61. 

SOLUTION:  

62. 

SOLUTION:  

63. 

SOLUTION:  

64. 

SOLUTION:  

65. 

SOLUTION:  

66. 

SOLUTION:  

Describe how the graph of each function is related to the graph of f (x) = x2.

67. g(x) = x2 − 8

SOLUTION:  

The graph of f (x) = x2 + c represents a vertical translation of the parent graph. The value of c is –8, and –8 < 0. If c

< 0, the graph of f (x) = x2 is translated  units down. Therefore, the graph of g(x) = x

2 – 8 is a translation of the

parent graph shifted down 8 units.

68. h(x) = x2

SOLUTION:  

The graph of f (x) = ax2 stretches or compresses the graph of f (x) = x

2 vertically. The value of a is , and 0 <  <

1. If 0 <  < 1, the graph of f (x) = x2 is compressed vertically. Therefore, the graph of h(x) = x

2 is the parent

graph compressed vertically.

69. h(x) = −x2 + 5

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is 5, and 5 > 0. If c > 0, the graph of f (x) = x2 is translated

 units up. Therefore, the graph of h(x) = −x2 + 5 is a translation of the parent graph shifted up 8 units and

reflected across the x-axis.

70. g(x) = (x + 10)2

SOLUTION:  

The graph of f (x) = (x – c)2 represents a horizontal translation of the parent graph. The value of c is –10, and –10 <

0. If c < 0, the graph of f (x) = (x – c)2

is translated  units left. Therefore, the graph of g(x) = (x + 10)2 is a

translation of the parent graph shifted left 10 units.

71. g(x) = −2x2

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = ax

2 stretches or

compresses the graph of f (x) = x2 vertically. The value of a is –2, and |–2| > 1. If  > 1, the graph of f (x) = x

2 is

stretched vertically. Therefore, the graph of g(x) = –2x2 is the parent graph reflected across the x-axis and stretched

vertically.

72. h(x) = −x2 −

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is , and < 0. If c < 0, the graph of f (x) = x2 is

translated  units down. Therefore, the graph of h(x) = −x2 is a translation of the parent graph shifted down

 units and reflected across the x-axis.

73. ROCK CLIMBING  While rock climbing, Damaris launches a grappling hook from a height of 6 feet with an initialupward velocity of 56 feet per second. The hook just misses the stone ledge that she wants to scale. As it falls, the hook anchors on a ledge 30 feet above the ground. How long was the hook in the air?

SOLUTION:  

A half second after she throws the hook, it is 30 feet in the air. The hook continues up, then drops back down to the height of 30 feet 3 seconds after the throw. The hook was in the air for 3 seconds.

Find each product.74. (b + 8)(b + 2)

SOLUTION:  

75. (x − 4)(x − 9)

SOLUTION:  

76. (y + 4)(y − 8)

SOLUTION:  

77. (p + 2)(p − 10)

SOLUTION:  

78. (2w − 5)(w + 7)

SOLUTION:  

79. (8d + 3)(5d + 2)

SOLUTION:  

80. BUSINESS  The amount of money spent at West Outlet Mall continues to increase. The total T(x) in millions of

dollars can be estimated by the function T(x) = 12(1.12)x, where x is the number of years after it opened in 2005.

Find the amount of sales in 2015, 2016, and 2017.

SOLUTION:  

The sales for the mall in 2015 will be about $37.27 million; in 2016 will be about $41.74 million; and in 2017 will be about $46.75 million.

Solve each proportion.

81. 

SOLUTION:  

82. 

SOLUTION:  

83. 

SOLUTION:  

84. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 27

10-5 The Pythagorean Theorem

Page 28: Find each missing length. If necessary, round to the ......Find each missing length. If necessary, round to the nearest hundredth. 62/87,21 Use the Pythagorean Theorem, substituting

Find each missing length. If necessary, round to the nearest hundredth.

1. 

SOLUTION:  Use the Pythagorean Theorem, substituting 3 for a and 4 for b.

2. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 21 for c.

3. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for b and 19 for c.

4. 

SOLUTION:  Use the Pythagorean Theorem, substituting 8 for a and 12 for b.

5. BASEBALL  A baseball diamond is a square. The distance between consecutive bases is 90 feet.

a.  How far does a catcher have to throw the ball from home plate to second base? b.  How far does a third baseman throw the ball to the first baseman from a point in the baseline 15 feet from third to second base? c.  A base runner going from first to second base is 100 feet from home plate. How far is the runner from second base?

SOLUTION:  a. Use the Pythagorean Theorem, substituting 90 for a and 90 for b.

The catcher has to throw the ball about 127 ft from home plate to second base.   b. The diagram below illustrates the throw made by the third baseman.

The length of a is 90 – 15 or 75 feet. Find the length of the throw c by using the Pythagorean Theorem, substituting 75 for a and 90 for b.

The third baseman has to throw the ball about 117 feet to the first baseman.   c. The diagram below illustrates the position of the base runner.

Use the Pythagorean Theorem to find the length of side a by substituting 90 for b and 100 for c.

So, the base runner is about 44 feet from first base to second base. Therefore, the distance the base runner is from second is about 90 – 44 or 46 feet.  

Determine whether each set of measures can be the lengths of the sides of a right triangle.6. 8, 12, 16

SOLUTION:  

Since the measure of the longest side is 16, let c = 16, a = 8, and b = 12. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 8, 12, and 16 is not a right triangle.

7. 28, 45, 53

SOLUTION:  

Since the measure of the longest side is 53, let c = 53, a = 28, and b = 45. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 28, 45, and 53 is a right triangle.

8. 7, 24, 25

SOLUTION:  

Since the measure of the longest side is 25, let c = 25, a = 7, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 7, 24, and 25 is a right triangle.

9. 15, 25, 45

SOLUTION:  

Since the measure of the longest side is 45, let c = 45, a = 15, and b = 25. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 15, 25, and 45 is not a right triangle.

Find each missing length. If necessary, round to the nearest hundredth.

10. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for a and 14 for b.

11. 

SOLUTION:  Use the Pythagorean Theorem, substituting 2 for a and 12 for c.

12. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and 20 for b.

13. 

SOLUTION:  Use the Pythagorean Theorem, substituting 9 for b and 31 for c.

14. 

SOLUTION:  Use the Pythagorean Theorem, substituting 16 for a and 26 for c.

15. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and  for b.

16. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for b and 25 for c.

17. 

SOLUTION:  

Use the Pythagorean Theorem, substituting 5 for a and  for c.

18. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for b and  for c.

19. TELEVISION  Larry is buying an entertainment stand for his television. The diagonal of his television is 42 inches. The space for the television measures 30 inches by 36 inches. Will Larry’s television fit? Explain.

SOLUTION:  Use the Pythagorean Theorem, substituting 30 for a and 36 for b.

Yes; sample answer: The diagonal of the space in the TV stand is about 46.9 inches, which is greater than the diagonal of the television, so Larry’s TV will fit.

Determine whether each set of measures can be the lengths of the sides of a right triangle. Then determine whether they form a Pythagorean triple.

20. 9, 40, 41

SOLUTION:  

Since the measure of the longest side is 41, let c = 41, a = 9, and b = 40. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 9, 40, and 41 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

21. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = 3, and b = . Then determine whether c2 = a

2 +

b2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 3, , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

22. 

SOLUTION:  

Since the measure of the longest side is 12, let c = 12, a = 4, and b = . Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 4, , and 12 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

23. 

SOLUTION:  

Since the measure of the longest side is 14, let c = 14, a = , and b = 7. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths , 7, and 14 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

24. 8, 31.5, 32.5

SOLUTION:  

Since the measure of the longest side is 32.5, let c = 32.5, a = 8, and b = 31.5. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 8, 31.5, and 32.5 is a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number, but b and c are not whole numbers.

25. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = , and b = . Then determine whether c2 =

a2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths , , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

26. 18, 24, 30

SOLUTION:  

Since the measure of the longest side is 30, let c = 30, a = 18, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 18, 24, and 30 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

27. 36, 77, 85

SOLUTION:  

Since the measure of the longest side is 85, let c = 85, a = 36, and b = 77. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 36, 77, and 85 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

28. 17, 33, 98

SOLUTION:  Since the measure of the longest side is 98, let c = 98, a = 17, and b = 33. The length of c is greater than the sum of a and b, so this is not a triangle. 

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 17, 33, and 98 is not a triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

29. GEOMETRY  Refer to the triangle shown.

a.  What is a? b.  Find the area of the triangle.

SOLUTION:  a. Use the Pythagorean Theorem, substituting 11 for b and 23 for c.

b.

The area of the triangle is about 111.1 units2.

30. GARDENING  Khaliah wants to plant flowers in a triangular plot. She has three lengths of plastic garden edging that measure 8 feet, 15 feet, and 17 feet. Determine whether these pieces form a right triangle. Explain.

SOLUTION:  Yes; sample answer: The longest side is 17 feet so this has to be the hypotenuse.

82 + 15

2 = 17

2 so the pieces form a right triangle by the converse of the Pythagorean Theorem.

31. LADDER  Mr. Takeo is locked out of his house. The only open window is on the second floor. There is a bush along the edge of the house, so he places the neighbor’s ladder 10 feet from the house. To the nearest foot, what length of ladder does he need to reach the window?

SOLUTION:  Use the Pythagorean Theorem, substituting 10 for a and 28 for b.

He will need a 30-ft ladder to reach the window.

CCSS TOOLS  Find the length of the hypotenuse. Round to the nearest hundredth.

32. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for a and 10 for b.

33. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 7 for b.

34. DOLLHOUSE  Alonso is building a dollhouse for his sister’s birthday. The roof is 24 inches across and the slanted side is 16 inches long as shown. Find the height of the roof to the nearest tenth of an inch.

SOLUTION:  Use the Pythagorean Theorem, substituting 12 for b and 16 for c.

The height of the roof is 10.6 in.

35. GEOMETRY  Each side of a cube is 5 inches long. Find the length of a diagonal of the cube.

SOLUTION:  

Use the Pythagorean Theorem to find the diagonal of a side of the cube, substituting 5 for a and 5 for b.

Then, use the Pythagorean Theorem to find a diagonal of the cube, substituting 5 for a and  for b.

The length of a diagonal of the cube is about 8.66 in.

36. TOWN SQUARES  The largest town square in the world is Tiananmen Square in Beijing, China, covering 98 acres. a.  One square mile is 640 acres. Assuming that Tiananmen Square is a square, how many feet long is a side to the nearest foot? b.  To the nearest foot, what is the diagonal distance across Tiananmen Square?

SOLUTION:  a. First, use the conversion factor 1 square mile = 640 acres to convert the area of the square from acres to square miles.

So, 98 acres is 0.153125 square miles. Use dimensional analysis to convert this measure to square feet.  

  Next, use the formula for the area of a square to find the length of a side.

Therefore, a side of Tiananmen Square is about 2066 feet long.   b. Use the Pythagorean Theorem to find the length of the diagonal of the square, substituting 2066 for both a and b.

The diagonal distance across Tiananmen Square is about 2922 feet.

37. TRUCKS  Violeta needs to construct a ramp to roll a cart of moving boxes from her garage into the back of her truck. The truck is 6 feet from the garage. The back of the truck is 36 inches above the ground. How long does the ramp have to be?

SOLUTION:  First, rewrite 36 inches as 3 ft. Use the Pythagorean thereom, substituting 6 for a and 3 for b.

The ramp must be about 6.7 ft.

If c is the measure of the hypotenuse of a right triangle, find each missing measure. If necessary, round to the nearest hundredth.

38. a = x, b = x + 41, c = 85

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 36; b = 77

39. a = 8, b = x, c = x + 2

SOLUTION:  

b = 15; c = 17

40. a = 12, b = x − 2, c = x

SOLUTION:  

b = 35; c = 37

41. a = x, b = x + 7, c = 97

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 65; b = 72

42. a = x − 47, b = x, c = x + 2

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 16; b = 63; c = 65

43. a = x − 32, b = x − 1, c = x

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 9; b = 40; c = 41

44. GEOMETRY  A right triangle has one leg that is 8 inches shorter than the other leg. The hypotenuse is 30 inches long. Find the length of each leg.

SOLUTION:  

The length of each leg of the triangle is about 24.83 in. and about 16.83 in.

45. MULTIPLE REPRESENTATIONS In this problem, you will derive a method for finding the midpoint and length of a segment on the coordinate plane. a. Graphical Use a graph to find the lengths of the segments between (3, 2) and (8, 2) and between (4, 1) and (4, 9).Then find the midpoint of each segment. b. Logical Use what you learned in part a to write expressions for the lengths of the segments between (x1 , y) and

(x2 , y) and between (x, y1 ) and (x,  y2). What would be the midpoint of each segment?

c. Analytical Based on your results from part b, find the midpoint of the segment with endpoints at (x1, y1), and (x2,

y2).

d. Analytical Use the Pythagorean Theorem to write an expression for the distance between (x1, y1), and (x2, y2).

SOLUTION:  a.  From the graph, the length of the vertical segment is 9 – 1 or 8 units and the length of the horizontal line is 8 – 3 or 5 units.

The midpoints will be located in the middle of each segment, or the average of the coordinates. For the vertical segment, the value between 1 and 9 is 5, so the midpoint should be at (4, 5). For the horizontal segment, the value between 3 and 8 is 5.5, so the midpoint should be at (5.5, 2). b.  Distance: The length of the segment between (x1, y) and (x2, y) will be the absolute value of x1 – x2. The length

of the segment between (x, y1) and (x, y2) will be the absolute value of y1 – y2.

Midpoint: When the x-coordinates are identical, then the x-coordinate of the midpoint will also be the same value.

This is true for the y-coordinates as well. The midpoint of (x1, y) and (x2, y) is at the average of the x-coordinates

and y or at , and the midpoint of (x, y1) and (x, y2) is at .

c. When the x- and y-coordinates are both different, the midpoint should be at the average values of the coordinates,

or at .   d. Form a right triangle with the segment formed by the two points as the hypotenuse. Note that the other coordinateis (x2, y1) in the drawing. 

 

We know the Pythagorean Theorem is a2 + b

2 = c

2. We can solve this formula for c by taking the square root of

each side. So, . Now we can replace the variables with the lengths of each side. The length of

side a is x2 – x1. The length of side b is y2 – y1. The length of side c is now .

 

46. ERROR ANALYSIS  Wyatt and Dario are determining whether 36, 77, and 85 form a Pythagorean triple. Is eitherof them correct? Explain your reasoning.

SOLUTION:  Wyatt is correct. The square of the greatest value should be equal to the sum of the squares of the two smaller values.  Since this is the case, the numbers form a Pythagorean triple.

47. CCSS PERSEVERANCE  Find the value of x in the figure shown.

SOLUTION:  The figure can be separated into two right triangles. Let m represent the missing side length common to both right

triangles. From the Pythagorean Theorem, m2 = 2

2 + x

2 and 14

2 = 8

2 + m

2. Using substitution, you can find that 2

2 +

x2 = 14

2 – 8

2.

Solve for x.

48. REASONING  Provide a counterexample to the statement. Any two right triangles with the same hypotenuse have the same area.

SOLUTION:  Different lengths of a and b can produce the same value of c in the Pythagorean theorem.  

 

Sample answer: A right triangle with legs measuring 3 cm and 4 cm has a hypotenuse of 5 cm and an area of 6 cm2.

A right triangle with legs measuring 2 cm and  cm also has a hypotenuse of 5 cm, but its area is   cm2,

which is not equivalent to 6 cm2.

49. OPEN ENDED  Draw a right triangle that has a hypotenuse of  units.

SOLUTION:  Use the Pythagorean Theorem to select two side lengths for a and b with the given value of c.

 

50. WRITING IN MATH  Explain how to determine whether segments in three lengths could form a right triangle.

SOLUTION:  

From the converse of the Pythagorean Theorem, if a2 + b

2 = c

2 then a, b, and c are the lengths of the side of a right

triangle. So, check to see whether the square of the greatest number is equal to the sum of the squares of the other two numbers. Consider triangle with sides of 9, 12 and 15 and a triangle with sides of 7, 13 and 19. 

   

51. GEOMETRY  Find the missing length.

A  −17

B  −

C  

D  17

SOLUTION:  

The correct choice is C.

52. What is a solution of this equation?

F  0, 3 G  3 H  0 J  no solutions

SOLUTION:  

The correct choice is H.

53. SHORT RESPONSE  A plumber charges $40 for the first hour of each house call plus $8 for each additional half hour. If the plumber works for 4 hours, how much does he charge?

SOLUTION:  Let x = the total number of hours worked.

The plumber charges $88 for 4 hours of work.

54. Find the next term in the geometric sequence .

A  

B  

C   

D  

SOLUTION:  

The correct choice is B.

Solve each equation. Check your solution.

55. 

SOLUTION:  

Check.

56. 

SOLUTION:  

Check.

57. 

SOLUTION:  

Check.

58. 

SOLUTION:  

Check.

59. 

SOLUTION:  

Check.

60. 

SOLUTION:  

Check.

There is no real solution.

Simplify each expression.

61. 

SOLUTION:  

62. 

SOLUTION:  

63. 

SOLUTION:  

64. 

SOLUTION:  

65. 

SOLUTION:  

66. 

SOLUTION:  

Describe how the graph of each function is related to the graph of f (x) = x2.

67. g(x) = x2 − 8

SOLUTION:  

The graph of f (x) = x2 + c represents a vertical translation of the parent graph. The value of c is –8, and –8 < 0. If c

< 0, the graph of f (x) = x2 is translated  units down. Therefore, the graph of g(x) = x

2 – 8 is a translation of the

parent graph shifted down 8 units.

68. h(x) = x2

SOLUTION:  

The graph of f (x) = ax2 stretches or compresses the graph of f (x) = x

2 vertically. The value of a is , and 0 <  <

1. If 0 <  < 1, the graph of f (x) = x2 is compressed vertically. Therefore, the graph of h(x) = x

2 is the parent

graph compressed vertically.

69. h(x) = −x2 + 5

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is 5, and 5 > 0. If c > 0, the graph of f (x) = x2 is translated

 units up. Therefore, the graph of h(x) = −x2 + 5 is a translation of the parent graph shifted up 8 units and

reflected across the x-axis.

70. g(x) = (x + 10)2

SOLUTION:  

The graph of f (x) = (x – c)2 represents a horizontal translation of the parent graph. The value of c is –10, and –10 <

0. If c < 0, the graph of f (x) = (x – c)2

is translated  units left. Therefore, the graph of g(x) = (x + 10)2 is a

translation of the parent graph shifted left 10 units.

71. g(x) = −2x2

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = ax

2 stretches or

compresses the graph of f (x) = x2 vertically. The value of a is –2, and |–2| > 1. If  > 1, the graph of f (x) = x

2 is

stretched vertically. Therefore, the graph of g(x) = –2x2 is the parent graph reflected across the x-axis and stretched

vertically.

72. h(x) = −x2 −

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is , and < 0. If c < 0, the graph of f (x) = x2 is

translated  units down. Therefore, the graph of h(x) = −x2 is a translation of the parent graph shifted down

 units and reflected across the x-axis.

73. ROCK CLIMBING  While rock climbing, Damaris launches a grappling hook from a height of 6 feet with an initialupward velocity of 56 feet per second. The hook just misses the stone ledge that she wants to scale. As it falls, the hook anchors on a ledge 30 feet above the ground. How long was the hook in the air?

SOLUTION:  

A half second after she throws the hook, it is 30 feet in the air. The hook continues up, then drops back down to the height of 30 feet 3 seconds after the throw. The hook was in the air for 3 seconds.

Find each product.74. (b + 8)(b + 2)

SOLUTION:  

75. (x − 4)(x − 9)

SOLUTION:  

76. (y + 4)(y − 8)

SOLUTION:  

77. (p + 2)(p − 10)

SOLUTION:  

78. (2w − 5)(w + 7)

SOLUTION:  

79. (8d + 3)(5d + 2)

SOLUTION:  

80. BUSINESS  The amount of money spent at West Outlet Mall continues to increase. The total T(x) in millions of

dollars can be estimated by the function T(x) = 12(1.12)x, where x is the number of years after it opened in 2005.

Find the amount of sales in 2015, 2016, and 2017.

SOLUTION:  

The sales for the mall in 2015 will be about $37.27 million; in 2016 will be about $41.74 million; and in 2017 will be about $46.75 million.

Solve each proportion.

81. 

SOLUTION:  

82. 

SOLUTION:  

83. 

SOLUTION:  

84. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 28

10-5 The Pythagorean Theorem

Page 29: Find each missing length. If necessary, round to the ......Find each missing length. If necessary, round to the nearest hundredth. 62/87,21 Use the Pythagorean Theorem, substituting

Find each missing length. If necessary, round to the nearest hundredth.

1. 

SOLUTION:  Use the Pythagorean Theorem, substituting 3 for a and 4 for b.

2. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 21 for c.

3. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for b and 19 for c.

4. 

SOLUTION:  Use the Pythagorean Theorem, substituting 8 for a and 12 for b.

5. BASEBALL  A baseball diamond is a square. The distance between consecutive bases is 90 feet.

a.  How far does a catcher have to throw the ball from home plate to second base? b.  How far does a third baseman throw the ball to the first baseman from a point in the baseline 15 feet from third to second base? c.  A base runner going from first to second base is 100 feet from home plate. How far is the runner from second base?

SOLUTION:  a. Use the Pythagorean Theorem, substituting 90 for a and 90 for b.

The catcher has to throw the ball about 127 ft from home plate to second base.   b. The diagram below illustrates the throw made by the third baseman.

The length of a is 90 – 15 or 75 feet. Find the length of the throw c by using the Pythagorean Theorem, substituting 75 for a and 90 for b.

The third baseman has to throw the ball about 117 feet to the first baseman.   c. The diagram below illustrates the position of the base runner.

Use the Pythagorean Theorem to find the length of side a by substituting 90 for b and 100 for c.

So, the base runner is about 44 feet from first base to second base. Therefore, the distance the base runner is from second is about 90 – 44 or 46 feet.  

Determine whether each set of measures can be the lengths of the sides of a right triangle.6. 8, 12, 16

SOLUTION:  

Since the measure of the longest side is 16, let c = 16, a = 8, and b = 12. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 8, 12, and 16 is not a right triangle.

7. 28, 45, 53

SOLUTION:  

Since the measure of the longest side is 53, let c = 53, a = 28, and b = 45. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 28, 45, and 53 is a right triangle.

8. 7, 24, 25

SOLUTION:  

Since the measure of the longest side is 25, let c = 25, a = 7, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 7, 24, and 25 is a right triangle.

9. 15, 25, 45

SOLUTION:  

Since the measure of the longest side is 45, let c = 45, a = 15, and b = 25. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 15, 25, and 45 is not a right triangle.

Find each missing length. If necessary, round to the nearest hundredth.

10. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for a and 14 for b.

11. 

SOLUTION:  Use the Pythagorean Theorem, substituting 2 for a and 12 for c.

12. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and 20 for b.

13. 

SOLUTION:  Use the Pythagorean Theorem, substituting 9 for b and 31 for c.

14. 

SOLUTION:  Use the Pythagorean Theorem, substituting 16 for a and 26 for c.

15. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and  for b.

16. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for b and 25 for c.

17. 

SOLUTION:  

Use the Pythagorean Theorem, substituting 5 for a and  for c.

18. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for b and  for c.

19. TELEVISION  Larry is buying an entertainment stand for his television. The diagonal of his television is 42 inches. The space for the television measures 30 inches by 36 inches. Will Larry’s television fit? Explain.

SOLUTION:  Use the Pythagorean Theorem, substituting 30 for a and 36 for b.

Yes; sample answer: The diagonal of the space in the TV stand is about 46.9 inches, which is greater than the diagonal of the television, so Larry’s TV will fit.

Determine whether each set of measures can be the lengths of the sides of a right triangle. Then determine whether they form a Pythagorean triple.

20. 9, 40, 41

SOLUTION:  

Since the measure of the longest side is 41, let c = 41, a = 9, and b = 40. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 9, 40, and 41 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

21. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = 3, and b = . Then determine whether c2 = a

2 +

b2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 3, , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

22. 

SOLUTION:  

Since the measure of the longest side is 12, let c = 12, a = 4, and b = . Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 4, , and 12 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

23. 

SOLUTION:  

Since the measure of the longest side is 14, let c = 14, a = , and b = 7. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths , 7, and 14 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

24. 8, 31.5, 32.5

SOLUTION:  

Since the measure of the longest side is 32.5, let c = 32.5, a = 8, and b = 31.5. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 8, 31.5, and 32.5 is a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number, but b and c are not whole numbers.

25. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = , and b = . Then determine whether c2 =

a2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths , , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

26. 18, 24, 30

SOLUTION:  

Since the measure of the longest side is 30, let c = 30, a = 18, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 18, 24, and 30 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

27. 36, 77, 85

SOLUTION:  

Since the measure of the longest side is 85, let c = 85, a = 36, and b = 77. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 36, 77, and 85 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

28. 17, 33, 98

SOLUTION:  Since the measure of the longest side is 98, let c = 98, a = 17, and b = 33. The length of c is greater than the sum of a and b, so this is not a triangle. 

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 17, 33, and 98 is not a triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

29. GEOMETRY  Refer to the triangle shown.

a.  What is a? b.  Find the area of the triangle.

SOLUTION:  a. Use the Pythagorean Theorem, substituting 11 for b and 23 for c.

b.

The area of the triangle is about 111.1 units2.

30. GARDENING  Khaliah wants to plant flowers in a triangular plot. She has three lengths of plastic garden edging that measure 8 feet, 15 feet, and 17 feet. Determine whether these pieces form a right triangle. Explain.

SOLUTION:  Yes; sample answer: The longest side is 17 feet so this has to be the hypotenuse.

82 + 15

2 = 17

2 so the pieces form a right triangle by the converse of the Pythagorean Theorem.

31. LADDER  Mr. Takeo is locked out of his house. The only open window is on the second floor. There is a bush along the edge of the house, so he places the neighbor’s ladder 10 feet from the house. To the nearest foot, what length of ladder does he need to reach the window?

SOLUTION:  Use the Pythagorean Theorem, substituting 10 for a and 28 for b.

He will need a 30-ft ladder to reach the window.

CCSS TOOLS  Find the length of the hypotenuse. Round to the nearest hundredth.

32. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for a and 10 for b.

33. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 7 for b.

34. DOLLHOUSE  Alonso is building a dollhouse for his sister’s birthday. The roof is 24 inches across and the slanted side is 16 inches long as shown. Find the height of the roof to the nearest tenth of an inch.

SOLUTION:  Use the Pythagorean Theorem, substituting 12 for b and 16 for c.

The height of the roof is 10.6 in.

35. GEOMETRY  Each side of a cube is 5 inches long. Find the length of a diagonal of the cube.

SOLUTION:  

Use the Pythagorean Theorem to find the diagonal of a side of the cube, substituting 5 for a and 5 for b.

Then, use the Pythagorean Theorem to find a diagonal of the cube, substituting 5 for a and  for b.

The length of a diagonal of the cube is about 8.66 in.

36. TOWN SQUARES  The largest town square in the world is Tiananmen Square in Beijing, China, covering 98 acres. a.  One square mile is 640 acres. Assuming that Tiananmen Square is a square, how many feet long is a side to the nearest foot? b.  To the nearest foot, what is the diagonal distance across Tiananmen Square?

SOLUTION:  a. First, use the conversion factor 1 square mile = 640 acres to convert the area of the square from acres to square miles.

So, 98 acres is 0.153125 square miles. Use dimensional analysis to convert this measure to square feet.  

  Next, use the formula for the area of a square to find the length of a side.

Therefore, a side of Tiananmen Square is about 2066 feet long.   b. Use the Pythagorean Theorem to find the length of the diagonal of the square, substituting 2066 for both a and b.

The diagonal distance across Tiananmen Square is about 2922 feet.

37. TRUCKS  Violeta needs to construct a ramp to roll a cart of moving boxes from her garage into the back of her truck. The truck is 6 feet from the garage. The back of the truck is 36 inches above the ground. How long does the ramp have to be?

SOLUTION:  First, rewrite 36 inches as 3 ft. Use the Pythagorean thereom, substituting 6 for a and 3 for b.

The ramp must be about 6.7 ft.

If c is the measure of the hypotenuse of a right triangle, find each missing measure. If necessary, round to the nearest hundredth.

38. a = x, b = x + 41, c = 85

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 36; b = 77

39. a = 8, b = x, c = x + 2

SOLUTION:  

b = 15; c = 17

40. a = 12, b = x − 2, c = x

SOLUTION:  

b = 35; c = 37

41. a = x, b = x + 7, c = 97

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 65; b = 72

42. a = x − 47, b = x, c = x + 2

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 16; b = 63; c = 65

43. a = x − 32, b = x − 1, c = x

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 9; b = 40; c = 41

44. GEOMETRY  A right triangle has one leg that is 8 inches shorter than the other leg. The hypotenuse is 30 inches long. Find the length of each leg.

SOLUTION:  

The length of each leg of the triangle is about 24.83 in. and about 16.83 in.

45. MULTIPLE REPRESENTATIONS In this problem, you will derive a method for finding the midpoint and length of a segment on the coordinate plane. a. Graphical Use a graph to find the lengths of the segments between (3, 2) and (8, 2) and between (4, 1) and (4, 9).Then find the midpoint of each segment. b. Logical Use what you learned in part a to write expressions for the lengths of the segments between (x1 , y) and

(x2 , y) and between (x, y1 ) and (x,  y2). What would be the midpoint of each segment?

c. Analytical Based on your results from part b, find the midpoint of the segment with endpoints at (x1, y1), and (x2,

y2).

d. Analytical Use the Pythagorean Theorem to write an expression for the distance between (x1, y1), and (x2, y2).

SOLUTION:  a.  From the graph, the length of the vertical segment is 9 – 1 or 8 units and the length of the horizontal line is 8 – 3 or 5 units.

The midpoints will be located in the middle of each segment, or the average of the coordinates. For the vertical segment, the value between 1 and 9 is 5, so the midpoint should be at (4, 5). For the horizontal segment, the value between 3 and 8 is 5.5, so the midpoint should be at (5.5, 2). b.  Distance: The length of the segment between (x1, y) and (x2, y) will be the absolute value of x1 – x2. The length

of the segment between (x, y1) and (x, y2) will be the absolute value of y1 – y2.

Midpoint: When the x-coordinates are identical, then the x-coordinate of the midpoint will also be the same value.

This is true for the y-coordinates as well. The midpoint of (x1, y) and (x2, y) is at the average of the x-coordinates

and y or at , and the midpoint of (x, y1) and (x, y2) is at .

c. When the x- and y-coordinates are both different, the midpoint should be at the average values of the coordinates,

or at .   d. Form a right triangle with the segment formed by the two points as the hypotenuse. Note that the other coordinateis (x2, y1) in the drawing. 

 

We know the Pythagorean Theorem is a2 + b

2 = c

2. We can solve this formula for c by taking the square root of

each side. So, . Now we can replace the variables with the lengths of each side. The length of

side a is x2 – x1. The length of side b is y2 – y1. The length of side c is now .

 

46. ERROR ANALYSIS  Wyatt and Dario are determining whether 36, 77, and 85 form a Pythagorean triple. Is eitherof them correct? Explain your reasoning.

SOLUTION:  Wyatt is correct. The square of the greatest value should be equal to the sum of the squares of the two smaller values.  Since this is the case, the numbers form a Pythagorean triple.

47. CCSS PERSEVERANCE  Find the value of x in the figure shown.

SOLUTION:  The figure can be separated into two right triangles. Let m represent the missing side length common to both right

triangles. From the Pythagorean Theorem, m2 = 2

2 + x

2 and 14

2 = 8

2 + m

2. Using substitution, you can find that 2

2 +

x2 = 14

2 – 8

2.

Solve for x.

48. REASONING  Provide a counterexample to the statement. Any two right triangles with the same hypotenuse have the same area.

SOLUTION:  Different lengths of a and b can produce the same value of c in the Pythagorean theorem.  

 

Sample answer: A right triangle with legs measuring 3 cm and 4 cm has a hypotenuse of 5 cm and an area of 6 cm2.

A right triangle with legs measuring 2 cm and  cm also has a hypotenuse of 5 cm, but its area is   cm2,

which is not equivalent to 6 cm2.

49. OPEN ENDED  Draw a right triangle that has a hypotenuse of  units.

SOLUTION:  Use the Pythagorean Theorem to select two side lengths for a and b with the given value of c.

 

50. WRITING IN MATH  Explain how to determine whether segments in three lengths could form a right triangle.

SOLUTION:  

From the converse of the Pythagorean Theorem, if a2 + b

2 = c

2 then a, b, and c are the lengths of the side of a right

triangle. So, check to see whether the square of the greatest number is equal to the sum of the squares of the other two numbers. Consider triangle with sides of 9, 12 and 15 and a triangle with sides of 7, 13 and 19. 

   

51. GEOMETRY  Find the missing length.

A  −17

B  −

C  

D  17

SOLUTION:  

The correct choice is C.

52. What is a solution of this equation?

F  0, 3 G  3 H  0 J  no solutions

SOLUTION:  

The correct choice is H.

53. SHORT RESPONSE  A plumber charges $40 for the first hour of each house call plus $8 for each additional half hour. If the plumber works for 4 hours, how much does he charge?

SOLUTION:  Let x = the total number of hours worked.

The plumber charges $88 for 4 hours of work.

54. Find the next term in the geometric sequence .

A  

B  

C   

D  

SOLUTION:  

The correct choice is B.

Solve each equation. Check your solution.

55. 

SOLUTION:  

Check.

56. 

SOLUTION:  

Check.

57. 

SOLUTION:  

Check.

58. 

SOLUTION:  

Check.

59. 

SOLUTION:  

Check.

60. 

SOLUTION:  

Check.

There is no real solution.

Simplify each expression.

61. 

SOLUTION:  

62. 

SOLUTION:  

63. 

SOLUTION:  

64. 

SOLUTION:  

65. 

SOLUTION:  

66. 

SOLUTION:  

Describe how the graph of each function is related to the graph of f (x) = x2.

67. g(x) = x2 − 8

SOLUTION:  

The graph of f (x) = x2 + c represents a vertical translation of the parent graph. The value of c is –8, and –8 < 0. If c

< 0, the graph of f (x) = x2 is translated  units down. Therefore, the graph of g(x) = x

2 – 8 is a translation of the

parent graph shifted down 8 units.

68. h(x) = x2

SOLUTION:  

The graph of f (x) = ax2 stretches or compresses the graph of f (x) = x

2 vertically. The value of a is , and 0 <  <

1. If 0 <  < 1, the graph of f (x) = x2 is compressed vertically. Therefore, the graph of h(x) = x

2 is the parent

graph compressed vertically.

69. h(x) = −x2 + 5

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is 5, and 5 > 0. If c > 0, the graph of f (x) = x2 is translated

 units up. Therefore, the graph of h(x) = −x2 + 5 is a translation of the parent graph shifted up 8 units and

reflected across the x-axis.

70. g(x) = (x + 10)2

SOLUTION:  

The graph of f (x) = (x – c)2 represents a horizontal translation of the parent graph. The value of c is –10, and –10 <

0. If c < 0, the graph of f (x) = (x – c)2

is translated  units left. Therefore, the graph of g(x) = (x + 10)2 is a

translation of the parent graph shifted left 10 units.

71. g(x) = −2x2

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = ax

2 stretches or

compresses the graph of f (x) = x2 vertically. The value of a is –2, and |–2| > 1. If  > 1, the graph of f (x) = x

2 is

stretched vertically. Therefore, the graph of g(x) = –2x2 is the parent graph reflected across the x-axis and stretched

vertically.

72. h(x) = −x2 −

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is , and < 0. If c < 0, the graph of f (x) = x2 is

translated  units down. Therefore, the graph of h(x) = −x2 is a translation of the parent graph shifted down

 units and reflected across the x-axis.

73. ROCK CLIMBING  While rock climbing, Damaris launches a grappling hook from a height of 6 feet with an initialupward velocity of 56 feet per second. The hook just misses the stone ledge that she wants to scale. As it falls, the hook anchors on a ledge 30 feet above the ground. How long was the hook in the air?

SOLUTION:  

A half second after she throws the hook, it is 30 feet in the air. The hook continues up, then drops back down to the height of 30 feet 3 seconds after the throw. The hook was in the air for 3 seconds.

Find each product.74. (b + 8)(b + 2)

SOLUTION:  

75. (x − 4)(x − 9)

SOLUTION:  

76. (y + 4)(y − 8)

SOLUTION:  

77. (p + 2)(p − 10)

SOLUTION:  

78. (2w − 5)(w + 7)

SOLUTION:  

79. (8d + 3)(5d + 2)

SOLUTION:  

80. BUSINESS  The amount of money spent at West Outlet Mall continues to increase. The total T(x) in millions of

dollars can be estimated by the function T(x) = 12(1.12)x, where x is the number of years after it opened in 2005.

Find the amount of sales in 2015, 2016, and 2017.

SOLUTION:  

The sales for the mall in 2015 will be about $37.27 million; in 2016 will be about $41.74 million; and in 2017 will be about $46.75 million.

Solve each proportion.

81. 

SOLUTION:  

82. 

SOLUTION:  

83. 

SOLUTION:  

84. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 29

10-5 The Pythagorean Theorem

Page 30: Find each missing length. If necessary, round to the ......Find each missing length. If necessary, round to the nearest hundredth. 62/87,21 Use the Pythagorean Theorem, substituting

Find each missing length. If necessary, round to the nearest hundredth.

1. 

SOLUTION:  Use the Pythagorean Theorem, substituting 3 for a and 4 for b.

2. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 21 for c.

3. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for b and 19 for c.

4. 

SOLUTION:  Use the Pythagorean Theorem, substituting 8 for a and 12 for b.

5. BASEBALL  A baseball diamond is a square. The distance between consecutive bases is 90 feet.

a.  How far does a catcher have to throw the ball from home plate to second base? b.  How far does a third baseman throw the ball to the first baseman from a point in the baseline 15 feet from third to second base? c.  A base runner going from first to second base is 100 feet from home plate. How far is the runner from second base?

SOLUTION:  a. Use the Pythagorean Theorem, substituting 90 for a and 90 for b.

The catcher has to throw the ball about 127 ft from home plate to second base.   b. The diagram below illustrates the throw made by the third baseman.

The length of a is 90 – 15 or 75 feet. Find the length of the throw c by using the Pythagorean Theorem, substituting 75 for a and 90 for b.

The third baseman has to throw the ball about 117 feet to the first baseman.   c. The diagram below illustrates the position of the base runner.

Use the Pythagorean Theorem to find the length of side a by substituting 90 for b and 100 for c.

So, the base runner is about 44 feet from first base to second base. Therefore, the distance the base runner is from second is about 90 – 44 or 46 feet.  

Determine whether each set of measures can be the lengths of the sides of a right triangle.6. 8, 12, 16

SOLUTION:  

Since the measure of the longest side is 16, let c = 16, a = 8, and b = 12. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 8, 12, and 16 is not a right triangle.

7. 28, 45, 53

SOLUTION:  

Since the measure of the longest side is 53, let c = 53, a = 28, and b = 45. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 28, 45, and 53 is a right triangle.

8. 7, 24, 25

SOLUTION:  

Since the measure of the longest side is 25, let c = 25, a = 7, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 7, 24, and 25 is a right triangle.

9. 15, 25, 45

SOLUTION:  

Since the measure of the longest side is 45, let c = 45, a = 15, and b = 25. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 15, 25, and 45 is not a right triangle.

Find each missing length. If necessary, round to the nearest hundredth.

10. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for a and 14 for b.

11. 

SOLUTION:  Use the Pythagorean Theorem, substituting 2 for a and 12 for c.

12. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and 20 for b.

13. 

SOLUTION:  Use the Pythagorean Theorem, substituting 9 for b and 31 for c.

14. 

SOLUTION:  Use the Pythagorean Theorem, substituting 16 for a and 26 for c.

15. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and  for b.

16. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for b and 25 for c.

17. 

SOLUTION:  

Use the Pythagorean Theorem, substituting 5 for a and  for c.

18. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for b and  for c.

19. TELEVISION  Larry is buying an entertainment stand for his television. The diagonal of his television is 42 inches. The space for the television measures 30 inches by 36 inches. Will Larry’s television fit? Explain.

SOLUTION:  Use the Pythagorean Theorem, substituting 30 for a and 36 for b.

Yes; sample answer: The diagonal of the space in the TV stand is about 46.9 inches, which is greater than the diagonal of the television, so Larry’s TV will fit.

Determine whether each set of measures can be the lengths of the sides of a right triangle. Then determine whether they form a Pythagorean triple.

20. 9, 40, 41

SOLUTION:  

Since the measure of the longest side is 41, let c = 41, a = 9, and b = 40. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 9, 40, and 41 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

21. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = 3, and b = . Then determine whether c2 = a

2 +

b2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 3, , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

22. 

SOLUTION:  

Since the measure of the longest side is 12, let c = 12, a = 4, and b = . Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 4, , and 12 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

23. 

SOLUTION:  

Since the measure of the longest side is 14, let c = 14, a = , and b = 7. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths , 7, and 14 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

24. 8, 31.5, 32.5

SOLUTION:  

Since the measure of the longest side is 32.5, let c = 32.5, a = 8, and b = 31.5. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 8, 31.5, and 32.5 is a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number, but b and c are not whole numbers.

25. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = , and b = . Then determine whether c2 =

a2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths , , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

26. 18, 24, 30

SOLUTION:  

Since the measure of the longest side is 30, let c = 30, a = 18, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 18, 24, and 30 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

27. 36, 77, 85

SOLUTION:  

Since the measure of the longest side is 85, let c = 85, a = 36, and b = 77. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 36, 77, and 85 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

28. 17, 33, 98

SOLUTION:  Since the measure of the longest side is 98, let c = 98, a = 17, and b = 33. The length of c is greater than the sum of a and b, so this is not a triangle. 

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 17, 33, and 98 is not a triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

29. GEOMETRY  Refer to the triangle shown.

a.  What is a? b.  Find the area of the triangle.

SOLUTION:  a. Use the Pythagorean Theorem, substituting 11 for b and 23 for c.

b.

The area of the triangle is about 111.1 units2.

30. GARDENING  Khaliah wants to plant flowers in a triangular plot. She has three lengths of plastic garden edging that measure 8 feet, 15 feet, and 17 feet. Determine whether these pieces form a right triangle. Explain.

SOLUTION:  Yes; sample answer: The longest side is 17 feet so this has to be the hypotenuse.

82 + 15

2 = 17

2 so the pieces form a right triangle by the converse of the Pythagorean Theorem.

31. LADDER  Mr. Takeo is locked out of his house. The only open window is on the second floor. There is a bush along the edge of the house, so he places the neighbor’s ladder 10 feet from the house. To the nearest foot, what length of ladder does he need to reach the window?

SOLUTION:  Use the Pythagorean Theorem, substituting 10 for a and 28 for b.

He will need a 30-ft ladder to reach the window.

CCSS TOOLS  Find the length of the hypotenuse. Round to the nearest hundredth.

32. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for a and 10 for b.

33. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 7 for b.

34. DOLLHOUSE  Alonso is building a dollhouse for his sister’s birthday. The roof is 24 inches across and the slanted side is 16 inches long as shown. Find the height of the roof to the nearest tenth of an inch.

SOLUTION:  Use the Pythagorean Theorem, substituting 12 for b and 16 for c.

The height of the roof is 10.6 in.

35. GEOMETRY  Each side of a cube is 5 inches long. Find the length of a diagonal of the cube.

SOLUTION:  

Use the Pythagorean Theorem to find the diagonal of a side of the cube, substituting 5 for a and 5 for b.

Then, use the Pythagorean Theorem to find a diagonal of the cube, substituting 5 for a and  for b.

The length of a diagonal of the cube is about 8.66 in.

36. TOWN SQUARES  The largest town square in the world is Tiananmen Square in Beijing, China, covering 98 acres. a.  One square mile is 640 acres. Assuming that Tiananmen Square is a square, how many feet long is a side to the nearest foot? b.  To the nearest foot, what is the diagonal distance across Tiananmen Square?

SOLUTION:  a. First, use the conversion factor 1 square mile = 640 acres to convert the area of the square from acres to square miles.

So, 98 acres is 0.153125 square miles. Use dimensional analysis to convert this measure to square feet.  

  Next, use the formula for the area of a square to find the length of a side.

Therefore, a side of Tiananmen Square is about 2066 feet long.   b. Use the Pythagorean Theorem to find the length of the diagonal of the square, substituting 2066 for both a and b.

The diagonal distance across Tiananmen Square is about 2922 feet.

37. TRUCKS  Violeta needs to construct a ramp to roll a cart of moving boxes from her garage into the back of her truck. The truck is 6 feet from the garage. The back of the truck is 36 inches above the ground. How long does the ramp have to be?

SOLUTION:  First, rewrite 36 inches as 3 ft. Use the Pythagorean thereom, substituting 6 for a and 3 for b.

The ramp must be about 6.7 ft.

If c is the measure of the hypotenuse of a right triangle, find each missing measure. If necessary, round to the nearest hundredth.

38. a = x, b = x + 41, c = 85

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 36; b = 77

39. a = 8, b = x, c = x + 2

SOLUTION:  

b = 15; c = 17

40. a = 12, b = x − 2, c = x

SOLUTION:  

b = 35; c = 37

41. a = x, b = x + 7, c = 97

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 65; b = 72

42. a = x − 47, b = x, c = x + 2

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 16; b = 63; c = 65

43. a = x − 32, b = x − 1, c = x

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 9; b = 40; c = 41

44. GEOMETRY  A right triangle has one leg that is 8 inches shorter than the other leg. The hypotenuse is 30 inches long. Find the length of each leg.

SOLUTION:  

The length of each leg of the triangle is about 24.83 in. and about 16.83 in.

45. MULTIPLE REPRESENTATIONS In this problem, you will derive a method for finding the midpoint and length of a segment on the coordinate plane. a. Graphical Use a graph to find the lengths of the segments between (3, 2) and (8, 2) and between (4, 1) and (4, 9).Then find the midpoint of each segment. b. Logical Use what you learned in part a to write expressions for the lengths of the segments between (x1 , y) and

(x2 , y) and between (x, y1 ) and (x,  y2). What would be the midpoint of each segment?

c. Analytical Based on your results from part b, find the midpoint of the segment with endpoints at (x1, y1), and (x2,

y2).

d. Analytical Use the Pythagorean Theorem to write an expression for the distance between (x1, y1), and (x2, y2).

SOLUTION:  a.  From the graph, the length of the vertical segment is 9 – 1 or 8 units and the length of the horizontal line is 8 – 3 or 5 units.

The midpoints will be located in the middle of each segment, or the average of the coordinates. For the vertical segment, the value between 1 and 9 is 5, so the midpoint should be at (4, 5). For the horizontal segment, the value between 3 and 8 is 5.5, so the midpoint should be at (5.5, 2). b.  Distance: The length of the segment between (x1, y) and (x2, y) will be the absolute value of x1 – x2. The length

of the segment between (x, y1) and (x, y2) will be the absolute value of y1 – y2.

Midpoint: When the x-coordinates are identical, then the x-coordinate of the midpoint will also be the same value.

This is true for the y-coordinates as well. The midpoint of (x1, y) and (x2, y) is at the average of the x-coordinates

and y or at , and the midpoint of (x, y1) and (x, y2) is at .

c. When the x- and y-coordinates are both different, the midpoint should be at the average values of the coordinates,

or at .   d. Form a right triangle with the segment formed by the two points as the hypotenuse. Note that the other coordinateis (x2, y1) in the drawing. 

 

We know the Pythagorean Theorem is a2 + b

2 = c

2. We can solve this formula for c by taking the square root of

each side. So, . Now we can replace the variables with the lengths of each side. The length of

side a is x2 – x1. The length of side b is y2 – y1. The length of side c is now .

 

46. ERROR ANALYSIS  Wyatt and Dario are determining whether 36, 77, and 85 form a Pythagorean triple. Is eitherof them correct? Explain your reasoning.

SOLUTION:  Wyatt is correct. The square of the greatest value should be equal to the sum of the squares of the two smaller values.  Since this is the case, the numbers form a Pythagorean triple.

47. CCSS PERSEVERANCE  Find the value of x in the figure shown.

SOLUTION:  The figure can be separated into two right triangles. Let m represent the missing side length common to both right

triangles. From the Pythagorean Theorem, m2 = 2

2 + x

2 and 14

2 = 8

2 + m

2. Using substitution, you can find that 2

2 +

x2 = 14

2 – 8

2.

Solve for x.

48. REASONING  Provide a counterexample to the statement. Any two right triangles with the same hypotenuse have the same area.

SOLUTION:  Different lengths of a and b can produce the same value of c in the Pythagorean theorem.  

 

Sample answer: A right triangle with legs measuring 3 cm and 4 cm has a hypotenuse of 5 cm and an area of 6 cm2.

A right triangle with legs measuring 2 cm and  cm also has a hypotenuse of 5 cm, but its area is   cm2,

which is not equivalent to 6 cm2.

49. OPEN ENDED  Draw a right triangle that has a hypotenuse of  units.

SOLUTION:  Use the Pythagorean Theorem to select two side lengths for a and b with the given value of c.

 

50. WRITING IN MATH  Explain how to determine whether segments in three lengths could form a right triangle.

SOLUTION:  

From the converse of the Pythagorean Theorem, if a2 + b

2 = c

2 then a, b, and c are the lengths of the side of a right

triangle. So, check to see whether the square of the greatest number is equal to the sum of the squares of the other two numbers. Consider triangle with sides of 9, 12 and 15 and a triangle with sides of 7, 13 and 19. 

   

51. GEOMETRY  Find the missing length.

A  −17

B  −

C  

D  17

SOLUTION:  

The correct choice is C.

52. What is a solution of this equation?

F  0, 3 G  3 H  0 J  no solutions

SOLUTION:  

The correct choice is H.

53. SHORT RESPONSE  A plumber charges $40 for the first hour of each house call plus $8 for each additional half hour. If the plumber works for 4 hours, how much does he charge?

SOLUTION:  Let x = the total number of hours worked.

The plumber charges $88 for 4 hours of work.

54. Find the next term in the geometric sequence .

A  

B  

C   

D  

SOLUTION:  

The correct choice is B.

Solve each equation. Check your solution.

55. 

SOLUTION:  

Check.

56. 

SOLUTION:  

Check.

57. 

SOLUTION:  

Check.

58. 

SOLUTION:  

Check.

59. 

SOLUTION:  

Check.

60. 

SOLUTION:  

Check.

There is no real solution.

Simplify each expression.

61. 

SOLUTION:  

62. 

SOLUTION:  

63. 

SOLUTION:  

64. 

SOLUTION:  

65. 

SOLUTION:  

66. 

SOLUTION:  

Describe how the graph of each function is related to the graph of f (x) = x2.

67. g(x) = x2 − 8

SOLUTION:  

The graph of f (x) = x2 + c represents a vertical translation of the parent graph. The value of c is –8, and –8 < 0. If c

< 0, the graph of f (x) = x2 is translated  units down. Therefore, the graph of g(x) = x

2 – 8 is a translation of the

parent graph shifted down 8 units.

68. h(x) = x2

SOLUTION:  

The graph of f (x) = ax2 stretches or compresses the graph of f (x) = x

2 vertically. The value of a is , and 0 <  <

1. If 0 <  < 1, the graph of f (x) = x2 is compressed vertically. Therefore, the graph of h(x) = x

2 is the parent

graph compressed vertically.

69. h(x) = −x2 + 5

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is 5, and 5 > 0. If c > 0, the graph of f (x) = x2 is translated

 units up. Therefore, the graph of h(x) = −x2 + 5 is a translation of the parent graph shifted up 8 units and

reflected across the x-axis.

70. g(x) = (x + 10)2

SOLUTION:  

The graph of f (x) = (x – c)2 represents a horizontal translation of the parent graph. The value of c is –10, and –10 <

0. If c < 0, the graph of f (x) = (x – c)2

is translated  units left. Therefore, the graph of g(x) = (x + 10)2 is a

translation of the parent graph shifted left 10 units.

71. g(x) = −2x2

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = ax

2 stretches or

compresses the graph of f (x) = x2 vertically. The value of a is –2, and |–2| > 1. If  > 1, the graph of f (x) = x

2 is

stretched vertically. Therefore, the graph of g(x) = –2x2 is the parent graph reflected across the x-axis and stretched

vertically.

72. h(x) = −x2 −

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is , and < 0. If c < 0, the graph of f (x) = x2 is

translated  units down. Therefore, the graph of h(x) = −x2 is a translation of the parent graph shifted down

 units and reflected across the x-axis.

73. ROCK CLIMBING  While rock climbing, Damaris launches a grappling hook from a height of 6 feet with an initialupward velocity of 56 feet per second. The hook just misses the stone ledge that she wants to scale. As it falls, the hook anchors on a ledge 30 feet above the ground. How long was the hook in the air?

SOLUTION:  

A half second after she throws the hook, it is 30 feet in the air. The hook continues up, then drops back down to the height of 30 feet 3 seconds after the throw. The hook was in the air for 3 seconds.

Find each product.74. (b + 8)(b + 2)

SOLUTION:  

75. (x − 4)(x − 9)

SOLUTION:  

76. (y + 4)(y − 8)

SOLUTION:  

77. (p + 2)(p − 10)

SOLUTION:  

78. (2w − 5)(w + 7)

SOLUTION:  

79. (8d + 3)(5d + 2)

SOLUTION:  

80. BUSINESS  The amount of money spent at West Outlet Mall continues to increase. The total T(x) in millions of

dollars can be estimated by the function T(x) = 12(1.12)x, where x is the number of years after it opened in 2005.

Find the amount of sales in 2015, 2016, and 2017.

SOLUTION:  

The sales for the mall in 2015 will be about $37.27 million; in 2016 will be about $41.74 million; and in 2017 will be about $46.75 million.

Solve each proportion.

81. 

SOLUTION:  

82. 

SOLUTION:  

83. 

SOLUTION:  

84. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 30

10-5 The Pythagorean Theorem

Page 31: Find each missing length. If necessary, round to the ......Find each missing length. If necessary, round to the nearest hundredth. 62/87,21 Use the Pythagorean Theorem, substituting

Find each missing length. If necessary, round to the nearest hundredth.

1. 

SOLUTION:  Use the Pythagorean Theorem, substituting 3 for a and 4 for b.

2. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 21 for c.

3. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for b and 19 for c.

4. 

SOLUTION:  Use the Pythagorean Theorem, substituting 8 for a and 12 for b.

5. BASEBALL  A baseball diamond is a square. The distance between consecutive bases is 90 feet.

a.  How far does a catcher have to throw the ball from home plate to second base? b.  How far does a third baseman throw the ball to the first baseman from a point in the baseline 15 feet from third to second base? c.  A base runner going from first to second base is 100 feet from home plate. How far is the runner from second base?

SOLUTION:  a. Use the Pythagorean Theorem, substituting 90 for a and 90 for b.

The catcher has to throw the ball about 127 ft from home plate to second base.   b. The diagram below illustrates the throw made by the third baseman.

The length of a is 90 – 15 or 75 feet. Find the length of the throw c by using the Pythagorean Theorem, substituting 75 for a and 90 for b.

The third baseman has to throw the ball about 117 feet to the first baseman.   c. The diagram below illustrates the position of the base runner.

Use the Pythagorean Theorem to find the length of side a by substituting 90 for b and 100 for c.

So, the base runner is about 44 feet from first base to second base. Therefore, the distance the base runner is from second is about 90 – 44 or 46 feet.  

Determine whether each set of measures can be the lengths of the sides of a right triangle.6. 8, 12, 16

SOLUTION:  

Since the measure of the longest side is 16, let c = 16, a = 8, and b = 12. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 8, 12, and 16 is not a right triangle.

7. 28, 45, 53

SOLUTION:  

Since the measure of the longest side is 53, let c = 53, a = 28, and b = 45. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 28, 45, and 53 is a right triangle.

8. 7, 24, 25

SOLUTION:  

Since the measure of the longest side is 25, let c = 25, a = 7, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 7, 24, and 25 is a right triangle.

9. 15, 25, 45

SOLUTION:  

Since the measure of the longest side is 45, let c = 45, a = 15, and b = 25. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 15, 25, and 45 is not a right triangle.

Find each missing length. If necessary, round to the nearest hundredth.

10. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for a and 14 for b.

11. 

SOLUTION:  Use the Pythagorean Theorem, substituting 2 for a and 12 for c.

12. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and 20 for b.

13. 

SOLUTION:  Use the Pythagorean Theorem, substituting 9 for b and 31 for c.

14. 

SOLUTION:  Use the Pythagorean Theorem, substituting 16 for a and 26 for c.

15. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and  for b.

16. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for b and 25 for c.

17. 

SOLUTION:  

Use the Pythagorean Theorem, substituting 5 for a and  for c.

18. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for b and  for c.

19. TELEVISION  Larry is buying an entertainment stand for his television. The diagonal of his television is 42 inches. The space for the television measures 30 inches by 36 inches. Will Larry’s television fit? Explain.

SOLUTION:  Use the Pythagorean Theorem, substituting 30 for a and 36 for b.

Yes; sample answer: The diagonal of the space in the TV stand is about 46.9 inches, which is greater than the diagonal of the television, so Larry’s TV will fit.

Determine whether each set of measures can be the lengths of the sides of a right triangle. Then determine whether they form a Pythagorean triple.

20. 9, 40, 41

SOLUTION:  

Since the measure of the longest side is 41, let c = 41, a = 9, and b = 40. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 9, 40, and 41 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

21. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = 3, and b = . Then determine whether c2 = a

2 +

b2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 3, , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

22. 

SOLUTION:  

Since the measure of the longest side is 12, let c = 12, a = 4, and b = . Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 4, , and 12 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

23. 

SOLUTION:  

Since the measure of the longest side is 14, let c = 14, a = , and b = 7. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths , 7, and 14 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

24. 8, 31.5, 32.5

SOLUTION:  

Since the measure of the longest side is 32.5, let c = 32.5, a = 8, and b = 31.5. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 8, 31.5, and 32.5 is a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number, but b and c are not whole numbers.

25. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = , and b = . Then determine whether c2 =

a2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths , , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

26. 18, 24, 30

SOLUTION:  

Since the measure of the longest side is 30, let c = 30, a = 18, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 18, 24, and 30 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

27. 36, 77, 85

SOLUTION:  

Since the measure of the longest side is 85, let c = 85, a = 36, and b = 77. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 36, 77, and 85 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

28. 17, 33, 98

SOLUTION:  Since the measure of the longest side is 98, let c = 98, a = 17, and b = 33. The length of c is greater than the sum of a and b, so this is not a triangle. 

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 17, 33, and 98 is not a triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

29. GEOMETRY  Refer to the triangle shown.

a.  What is a? b.  Find the area of the triangle.

SOLUTION:  a. Use the Pythagorean Theorem, substituting 11 for b and 23 for c.

b.

The area of the triangle is about 111.1 units2.

30. GARDENING  Khaliah wants to plant flowers in a triangular plot. She has three lengths of plastic garden edging that measure 8 feet, 15 feet, and 17 feet. Determine whether these pieces form a right triangle. Explain.

SOLUTION:  Yes; sample answer: The longest side is 17 feet so this has to be the hypotenuse.

82 + 15

2 = 17

2 so the pieces form a right triangle by the converse of the Pythagorean Theorem.

31. LADDER  Mr. Takeo is locked out of his house. The only open window is on the second floor. There is a bush along the edge of the house, so he places the neighbor’s ladder 10 feet from the house. To the nearest foot, what length of ladder does he need to reach the window?

SOLUTION:  Use the Pythagorean Theorem, substituting 10 for a and 28 for b.

He will need a 30-ft ladder to reach the window.

CCSS TOOLS  Find the length of the hypotenuse. Round to the nearest hundredth.

32. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for a and 10 for b.

33. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 7 for b.

34. DOLLHOUSE  Alonso is building a dollhouse for his sister’s birthday. The roof is 24 inches across and the slanted side is 16 inches long as shown. Find the height of the roof to the nearest tenth of an inch.

SOLUTION:  Use the Pythagorean Theorem, substituting 12 for b and 16 for c.

The height of the roof is 10.6 in.

35. GEOMETRY  Each side of a cube is 5 inches long. Find the length of a diagonal of the cube.

SOLUTION:  

Use the Pythagorean Theorem to find the diagonal of a side of the cube, substituting 5 for a and 5 for b.

Then, use the Pythagorean Theorem to find a diagonal of the cube, substituting 5 for a and  for b.

The length of a diagonal of the cube is about 8.66 in.

36. TOWN SQUARES  The largest town square in the world is Tiananmen Square in Beijing, China, covering 98 acres. a.  One square mile is 640 acres. Assuming that Tiananmen Square is a square, how many feet long is a side to the nearest foot? b.  To the nearest foot, what is the diagonal distance across Tiananmen Square?

SOLUTION:  a. First, use the conversion factor 1 square mile = 640 acres to convert the area of the square from acres to square miles.

So, 98 acres is 0.153125 square miles. Use dimensional analysis to convert this measure to square feet.  

  Next, use the formula for the area of a square to find the length of a side.

Therefore, a side of Tiananmen Square is about 2066 feet long.   b. Use the Pythagorean Theorem to find the length of the diagonal of the square, substituting 2066 for both a and b.

The diagonal distance across Tiananmen Square is about 2922 feet.

37. TRUCKS  Violeta needs to construct a ramp to roll a cart of moving boxes from her garage into the back of her truck. The truck is 6 feet from the garage. The back of the truck is 36 inches above the ground. How long does the ramp have to be?

SOLUTION:  First, rewrite 36 inches as 3 ft. Use the Pythagorean thereom, substituting 6 for a and 3 for b.

The ramp must be about 6.7 ft.

If c is the measure of the hypotenuse of a right triangle, find each missing measure. If necessary, round to the nearest hundredth.

38. a = x, b = x + 41, c = 85

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 36; b = 77

39. a = 8, b = x, c = x + 2

SOLUTION:  

b = 15; c = 17

40. a = 12, b = x − 2, c = x

SOLUTION:  

b = 35; c = 37

41. a = x, b = x + 7, c = 97

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 65; b = 72

42. a = x − 47, b = x, c = x + 2

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 16; b = 63; c = 65

43. a = x − 32, b = x − 1, c = x

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 9; b = 40; c = 41

44. GEOMETRY  A right triangle has one leg that is 8 inches shorter than the other leg. The hypotenuse is 30 inches long. Find the length of each leg.

SOLUTION:  

The length of each leg of the triangle is about 24.83 in. and about 16.83 in.

45. MULTIPLE REPRESENTATIONS In this problem, you will derive a method for finding the midpoint and length of a segment on the coordinate plane. a. Graphical Use a graph to find the lengths of the segments between (3, 2) and (8, 2) and between (4, 1) and (4, 9).Then find the midpoint of each segment. b. Logical Use what you learned in part a to write expressions for the lengths of the segments between (x1 , y) and

(x2 , y) and between (x, y1 ) and (x,  y2). What would be the midpoint of each segment?

c. Analytical Based on your results from part b, find the midpoint of the segment with endpoints at (x1, y1), and (x2,

y2).

d. Analytical Use the Pythagorean Theorem to write an expression for the distance between (x1, y1), and (x2, y2).

SOLUTION:  a.  From the graph, the length of the vertical segment is 9 – 1 or 8 units and the length of the horizontal line is 8 – 3 or 5 units.

The midpoints will be located in the middle of each segment, or the average of the coordinates. For the vertical segment, the value between 1 and 9 is 5, so the midpoint should be at (4, 5). For the horizontal segment, the value between 3 and 8 is 5.5, so the midpoint should be at (5.5, 2). b.  Distance: The length of the segment between (x1, y) and (x2, y) will be the absolute value of x1 – x2. The length

of the segment between (x, y1) and (x, y2) will be the absolute value of y1 – y2.

Midpoint: When the x-coordinates are identical, then the x-coordinate of the midpoint will also be the same value.

This is true for the y-coordinates as well. The midpoint of (x1, y) and (x2, y) is at the average of the x-coordinates

and y or at , and the midpoint of (x, y1) and (x, y2) is at .

c. When the x- and y-coordinates are both different, the midpoint should be at the average values of the coordinates,

or at .   d. Form a right triangle with the segment formed by the two points as the hypotenuse. Note that the other coordinateis (x2, y1) in the drawing. 

 

We know the Pythagorean Theorem is a2 + b

2 = c

2. We can solve this formula for c by taking the square root of

each side. So, . Now we can replace the variables with the lengths of each side. The length of

side a is x2 – x1. The length of side b is y2 – y1. The length of side c is now .

 

46. ERROR ANALYSIS  Wyatt and Dario are determining whether 36, 77, and 85 form a Pythagorean triple. Is eitherof them correct? Explain your reasoning.

SOLUTION:  Wyatt is correct. The square of the greatest value should be equal to the sum of the squares of the two smaller values.  Since this is the case, the numbers form a Pythagorean triple.

47. CCSS PERSEVERANCE  Find the value of x in the figure shown.

SOLUTION:  The figure can be separated into two right triangles. Let m represent the missing side length common to both right

triangles. From the Pythagorean Theorem, m2 = 2

2 + x

2 and 14

2 = 8

2 + m

2. Using substitution, you can find that 2

2 +

x2 = 14

2 – 8

2.

Solve for x.

48. REASONING  Provide a counterexample to the statement. Any two right triangles with the same hypotenuse have the same area.

SOLUTION:  Different lengths of a and b can produce the same value of c in the Pythagorean theorem.  

 

Sample answer: A right triangle with legs measuring 3 cm and 4 cm has a hypotenuse of 5 cm and an area of 6 cm2.

A right triangle with legs measuring 2 cm and  cm also has a hypotenuse of 5 cm, but its area is   cm2,

which is not equivalent to 6 cm2.

49. OPEN ENDED  Draw a right triangle that has a hypotenuse of  units.

SOLUTION:  Use the Pythagorean Theorem to select two side lengths for a and b with the given value of c.

 

50. WRITING IN MATH  Explain how to determine whether segments in three lengths could form a right triangle.

SOLUTION:  

From the converse of the Pythagorean Theorem, if a2 + b

2 = c

2 then a, b, and c are the lengths of the side of a right

triangle. So, check to see whether the square of the greatest number is equal to the sum of the squares of the other two numbers. Consider triangle with sides of 9, 12 and 15 and a triangle with sides of 7, 13 and 19. 

   

51. GEOMETRY  Find the missing length.

A  −17

B  −

C  

D  17

SOLUTION:  

The correct choice is C.

52. What is a solution of this equation?

F  0, 3 G  3 H  0 J  no solutions

SOLUTION:  

The correct choice is H.

53. SHORT RESPONSE  A plumber charges $40 for the first hour of each house call plus $8 for each additional half hour. If the plumber works for 4 hours, how much does he charge?

SOLUTION:  Let x = the total number of hours worked.

The plumber charges $88 for 4 hours of work.

54. Find the next term in the geometric sequence .

A  

B  

C   

D  

SOLUTION:  

The correct choice is B.

Solve each equation. Check your solution.

55. 

SOLUTION:  

Check.

56. 

SOLUTION:  

Check.

57. 

SOLUTION:  

Check.

58. 

SOLUTION:  

Check.

59. 

SOLUTION:  

Check.

60. 

SOLUTION:  

Check.

There is no real solution.

Simplify each expression.

61. 

SOLUTION:  

62. 

SOLUTION:  

63. 

SOLUTION:  

64. 

SOLUTION:  

65. 

SOLUTION:  

66. 

SOLUTION:  

Describe how the graph of each function is related to the graph of f (x) = x2.

67. g(x) = x2 − 8

SOLUTION:  

The graph of f (x) = x2 + c represents a vertical translation of the parent graph. The value of c is –8, and –8 < 0. If c

< 0, the graph of f (x) = x2 is translated  units down. Therefore, the graph of g(x) = x

2 – 8 is a translation of the

parent graph shifted down 8 units.

68. h(x) = x2

SOLUTION:  

The graph of f (x) = ax2 stretches or compresses the graph of f (x) = x

2 vertically. The value of a is , and 0 <  <

1. If 0 <  < 1, the graph of f (x) = x2 is compressed vertically. Therefore, the graph of h(x) = x

2 is the parent

graph compressed vertically.

69. h(x) = −x2 + 5

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is 5, and 5 > 0. If c > 0, the graph of f (x) = x2 is translated

 units up. Therefore, the graph of h(x) = −x2 + 5 is a translation of the parent graph shifted up 8 units and

reflected across the x-axis.

70. g(x) = (x + 10)2

SOLUTION:  

The graph of f (x) = (x – c)2 represents a horizontal translation of the parent graph. The value of c is –10, and –10 <

0. If c < 0, the graph of f (x) = (x – c)2

is translated  units left. Therefore, the graph of g(x) = (x + 10)2 is a

translation of the parent graph shifted left 10 units.

71. g(x) = −2x2

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = ax

2 stretches or

compresses the graph of f (x) = x2 vertically. The value of a is –2, and |–2| > 1. If  > 1, the graph of f (x) = x

2 is

stretched vertically. Therefore, the graph of g(x) = –2x2 is the parent graph reflected across the x-axis and stretched

vertically.

72. h(x) = −x2 −

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is , and < 0. If c < 0, the graph of f (x) = x2 is

translated  units down. Therefore, the graph of h(x) = −x2 is a translation of the parent graph shifted down

 units and reflected across the x-axis.

73. ROCK CLIMBING  While rock climbing, Damaris launches a grappling hook from a height of 6 feet with an initialupward velocity of 56 feet per second. The hook just misses the stone ledge that she wants to scale. As it falls, the hook anchors on a ledge 30 feet above the ground. How long was the hook in the air?

SOLUTION:  

A half second after she throws the hook, it is 30 feet in the air. The hook continues up, then drops back down to the height of 30 feet 3 seconds after the throw. The hook was in the air for 3 seconds.

Find each product.74. (b + 8)(b + 2)

SOLUTION:  

75. (x − 4)(x − 9)

SOLUTION:  

76. (y + 4)(y − 8)

SOLUTION:  

77. (p + 2)(p − 10)

SOLUTION:  

78. (2w − 5)(w + 7)

SOLUTION:  

79. (8d + 3)(5d + 2)

SOLUTION:  

80. BUSINESS  The amount of money spent at West Outlet Mall continues to increase. The total T(x) in millions of

dollars can be estimated by the function T(x) = 12(1.12)x, where x is the number of years after it opened in 2005.

Find the amount of sales in 2015, 2016, and 2017.

SOLUTION:  

The sales for the mall in 2015 will be about $37.27 million; in 2016 will be about $41.74 million; and in 2017 will be about $46.75 million.

Solve each proportion.

81. 

SOLUTION:  

82. 

SOLUTION:  

83. 

SOLUTION:  

84. 

SOLUTION:  

eSolutions Manual - Powered by Cognero Page 31

10-5 The Pythagorean Theorem

Page 32: Find each missing length. If necessary, round to the ......Find each missing length. If necessary, round to the nearest hundredth. 62/87,21 Use the Pythagorean Theorem, substituting

Find each missing length. If necessary, round to the nearest hundredth.

1. 

SOLUTION:  Use the Pythagorean Theorem, substituting 3 for a and 4 for b.

2. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 21 for c.

3. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for b and 19 for c.

4. 

SOLUTION:  Use the Pythagorean Theorem, substituting 8 for a and 12 for b.

5. BASEBALL  A baseball diamond is a square. The distance between consecutive bases is 90 feet.

a.  How far does a catcher have to throw the ball from home plate to second base? b.  How far does a third baseman throw the ball to the first baseman from a point in the baseline 15 feet from third to second base? c.  A base runner going from first to second base is 100 feet from home plate. How far is the runner from second base?

SOLUTION:  a. Use the Pythagorean Theorem, substituting 90 for a and 90 for b.

The catcher has to throw the ball about 127 ft from home plate to second base.   b. The diagram below illustrates the throw made by the third baseman.

The length of a is 90 – 15 or 75 feet. Find the length of the throw c by using the Pythagorean Theorem, substituting 75 for a and 90 for b.

The third baseman has to throw the ball about 117 feet to the first baseman.   c. The diagram below illustrates the position of the base runner.

Use the Pythagorean Theorem to find the length of side a by substituting 90 for b and 100 for c.

So, the base runner is about 44 feet from first base to second base. Therefore, the distance the base runner is from second is about 90 – 44 or 46 feet.  

Determine whether each set of measures can be the lengths of the sides of a right triangle.6. 8, 12, 16

SOLUTION:  

Since the measure of the longest side is 16, let c = 16, a = 8, and b = 12. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 8, 12, and 16 is not a right triangle.

7. 28, 45, 53

SOLUTION:  

Since the measure of the longest side is 53, let c = 53, a = 28, and b = 45. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 28, 45, and 53 is a right triangle.

8. 7, 24, 25

SOLUTION:  

Since the measure of the longest side is 25, let c = 25, a = 7, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 7, 24, and 25 is a right triangle.

9. 15, 25, 45

SOLUTION:  

Since the measure of the longest side is 45, let c = 45, a = 15, and b = 25. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 15, 25, and 45 is not a right triangle.

Find each missing length. If necessary, round to the nearest hundredth.

10. 

SOLUTION:  Use the Pythagorean Theorem, substituting 6 for a and 14 for b.

11. 

SOLUTION:  Use the Pythagorean Theorem, substituting 2 for a and 12 for c.

12. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and 20 for b.

13. 

SOLUTION:  Use the Pythagorean Theorem, substituting 9 for b and 31 for c.

14. 

SOLUTION:  Use the Pythagorean Theorem, substituting 16 for a and 26 for c.

15. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for a and  for b.

16. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for b and 25 for c.

17. 

SOLUTION:  

Use the Pythagorean Theorem, substituting 5 for a and  for c.

18. 

SOLUTION:  

Use the Pythagorean Theorem, substituting  for b and  for c.

19. TELEVISION  Larry is buying an entertainment stand for his television. The diagonal of his television is 42 inches. The space for the television measures 30 inches by 36 inches. Will Larry’s television fit? Explain.

SOLUTION:  Use the Pythagorean Theorem, substituting 30 for a and 36 for b.

Yes; sample answer: The diagonal of the space in the TV stand is about 46.9 inches, which is greater than the diagonal of the television, so Larry’s TV will fit.

Determine whether each set of measures can be the lengths of the sides of a right triangle. Then determine whether they form a Pythagorean triple.

20. 9, 40, 41

SOLUTION:  

Since the measure of the longest side is 41, let c = 41, a = 9, and b = 40. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 9, 40, and 41 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

21. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = 3, and b = . Then determine whether c2 = a

2 +

b2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths 3, , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

22. 

SOLUTION:  

Since the measure of the longest side is 12, let c = 12, a = 4, and b = . Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 4, , and 12 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

23. 

SOLUTION:  

Since the measure of the longest side is 14, let c = 14, a = , and b = 7. Then determine whether c2 = a

2 + b

2.

No, because c2 ≠ a2

+ b2, a triangle with side lengths , 7, and 14 is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

24. 8, 31.5, 32.5

SOLUTION:  

Since the measure of the longest side is 32.5, let c = 32.5, a = 8, and b = 31.5. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 8, 31.5, and 32.5 is a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number, but b and c are not whole numbers.

25. 

SOLUTION:  

Since the measure of the longest side is , let c = , a = , and b = . Then determine whether c2 =

a2 + b

2.

No, because c2 ≠ a

2 + b

2, a triangle with side lengths , , and  is not a right triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

26. 18, 24, 30

SOLUTION:  

Since the measure of the longest side is 30, let c = 30, a = 18, and b = 24. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 18, 24, and 30 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

27. 36, 77, 85

SOLUTION:  

Since the measure of the longest side is 85, let c = 85, a = 36, and b = 77. Then determine whether c2 = a

2 + b

2.

Yes, because c2 = a

2 + b

2, a triangle with side lengths 36, 77, and 85 is a right triangle.

Yes, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

28. 17, 33, 98

SOLUTION:  Since the measure of the longest side is 98, let c = 98, a = 17, and b = 33. The length of c is greater than the sum of a and b, so this is not a triangle. 

No, because c2 ≠ a

2 + b

2, a triangle with side lengths 17, 33, and 98 is not a triangle.

No, because a Pythagorean triple is a group of three whole numbers that satisfy the equation c2 = a

2 + b

2, where c

is the greatest number.

29. GEOMETRY  Refer to the triangle shown.

a.  What is a? b.  Find the area of the triangle.

SOLUTION:  a. Use the Pythagorean Theorem, substituting 11 for b and 23 for c.

b.

The area of the triangle is about 111.1 units2.

30. GARDENING  Khaliah wants to plant flowers in a triangular plot. She has three lengths of plastic garden edging that measure 8 feet, 15 feet, and 17 feet. Determine whether these pieces form a right triangle. Explain.

SOLUTION:  Yes; sample answer: The longest side is 17 feet so this has to be the hypotenuse.

82 + 15

2 = 17

2 so the pieces form a right triangle by the converse of the Pythagorean Theorem.

31. LADDER  Mr. Takeo is locked out of his house. The only open window is on the second floor. There is a bush along the edge of the house, so he places the neighbor’s ladder 10 feet from the house. To the nearest foot, what length of ladder does he need to reach the window?

SOLUTION:  Use the Pythagorean Theorem, substituting 10 for a and 28 for b.

He will need a 30-ft ladder to reach the window.

CCSS TOOLS  Find the length of the hypotenuse. Round to the nearest hundredth.

32. 

SOLUTION:  Use the Pythagorean Theorem, substituting 7 for a and 10 for b.

33. 

SOLUTION:  Use the Pythagorean Theorem, substituting 4 for a and 7 for b.

34. DOLLHOUSE  Alonso is building a dollhouse for his sister’s birthday. The roof is 24 inches across and the slanted side is 16 inches long as shown. Find the height of the roof to the nearest tenth of an inch.

SOLUTION:  Use the Pythagorean Theorem, substituting 12 for b and 16 for c.

The height of the roof is 10.6 in.

35. GEOMETRY  Each side of a cube is 5 inches long. Find the length of a diagonal of the cube.

SOLUTION:  

Use the Pythagorean Theorem to find the diagonal of a side of the cube, substituting 5 for a and 5 for b.

Then, use the Pythagorean Theorem to find a diagonal of the cube, substituting 5 for a and  for b.

The length of a diagonal of the cube is about 8.66 in.

36. TOWN SQUARES  The largest town square in the world is Tiananmen Square in Beijing, China, covering 98 acres. a.  One square mile is 640 acres. Assuming that Tiananmen Square is a square, how many feet long is a side to the nearest foot? b.  To the nearest foot, what is the diagonal distance across Tiananmen Square?

SOLUTION:  a. First, use the conversion factor 1 square mile = 640 acres to convert the area of the square from acres to square miles.

So, 98 acres is 0.153125 square miles. Use dimensional analysis to convert this measure to square feet.  

  Next, use the formula for the area of a square to find the length of a side.

Therefore, a side of Tiananmen Square is about 2066 feet long.   b. Use the Pythagorean Theorem to find the length of the diagonal of the square, substituting 2066 for both a and b.

The diagonal distance across Tiananmen Square is about 2922 feet.

37. TRUCKS  Violeta needs to construct a ramp to roll a cart of moving boxes from her garage into the back of her truck. The truck is 6 feet from the garage. The back of the truck is 36 inches above the ground. How long does the ramp have to be?

SOLUTION:  First, rewrite 36 inches as 3 ft. Use the Pythagorean thereom, substituting 6 for a and 3 for b.

The ramp must be about 6.7 ft.

If c is the measure of the hypotenuse of a right triangle, find each missing measure. If necessary, round to the nearest hundredth.

38. a = x, b = x + 41, c = 85

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 36; b = 77

39. a = 8, b = x, c = x + 2

SOLUTION:  

b = 15; c = 17

40. a = 12, b = x − 2, c = x

SOLUTION:  

b = 35; c = 37

41. a = x, b = x + 7, c = 97

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 65; b = 72

42. a = x − 47, b = x, c = x + 2

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 16; b = 63; c = 65

43. a = x − 32, b = x − 1, c = x

SOLUTION:  

Use the Zero Product Property to solve for x.  a = 9; b = 40; c = 41

44. GEOMETRY  A right triangle has one leg that is 8 inches shorter than the other leg. The hypotenuse is 30 inches long. Find the length of each leg.

SOLUTION:  

The length of each leg of the triangle is about 24.83 in. and about 16.83 in.

45. MULTIPLE REPRESENTATIONS In this problem, you will derive a method for finding the midpoint and length of a segment on the coordinate plane. a. Graphical Use a graph to find the lengths of the segments between (3, 2) and (8, 2) and between (4, 1) and (4, 9).Then find the midpoint of each segment. b. Logical Use what you learned in part a to write expressions for the lengths of the segments between (x1 , y) and

(x2 , y) and between (x, y1 ) and (x,  y2). What would be the midpoint of each segment?

c. Analytical Based on your results from part b, find the midpoint of the segment with endpoints at (x1, y1), and (x2,

y2).

d. Analytical Use the Pythagorean Theorem to write an expression for the distance between (x1, y1), and (x2, y2).

SOLUTION:  a.  From the graph, the length of the vertical segment is 9 – 1 or 8 units and the length of the horizontal line is 8 – 3 or 5 units.

The midpoints will be located in the middle of each segment, or the average of the coordinates. For the vertical segment, the value between 1 and 9 is 5, so the midpoint should be at (4, 5). For the horizontal segment, the value between 3 and 8 is 5.5, so the midpoint should be at (5.5, 2). b.  Distance: The length of the segment between (x1, y) and (x2, y) will be the absolute value of x1 – x2. The length

of the segment between (x, y1) and (x, y2) will be the absolute value of y1 – y2.

Midpoint: When the x-coordinates are identical, then the x-coordinate of the midpoint will also be the same value.

This is true for the y-coordinates as well. The midpoint of (x1, y) and (x2, y) is at the average of the x-coordinates

and y or at , and the midpoint of (x, y1) and (x, y2) is at .

c. When the x- and y-coordinates are both different, the midpoint should be at the average values of the coordinates,

or at .   d. Form a right triangle with the segment formed by the two points as the hypotenuse. Note that the other coordinateis (x2, y1) in the drawing. 

 

We know the Pythagorean Theorem is a2 + b

2 = c

2. We can solve this formula for c by taking the square root of

each side. So, . Now we can replace the variables with the lengths of each side. The length of

side a is x2 – x1. The length of side b is y2 – y1. The length of side c is now .

 

46. ERROR ANALYSIS  Wyatt and Dario are determining whether 36, 77, and 85 form a Pythagorean triple. Is eitherof them correct? Explain your reasoning.

SOLUTION:  Wyatt is correct. The square of the greatest value should be equal to the sum of the squares of the two smaller values.  Since this is the case, the numbers form a Pythagorean triple.

47. CCSS PERSEVERANCE  Find the value of x in the figure shown.

SOLUTION:  The figure can be separated into two right triangles. Let m represent the missing side length common to both right

triangles. From the Pythagorean Theorem, m2 = 2

2 + x

2 and 14

2 = 8

2 + m

2. Using substitution, you can find that 2

2 +

x2 = 14

2 – 8

2.

Solve for x.

48. REASONING  Provide a counterexample to the statement. Any two right triangles with the same hypotenuse have the same area.

SOLUTION:  Different lengths of a and b can produce the same value of c in the Pythagorean theorem.  

 

Sample answer: A right triangle with legs measuring 3 cm and 4 cm has a hypotenuse of 5 cm and an area of 6 cm2.

A right triangle with legs measuring 2 cm and  cm also has a hypotenuse of 5 cm, but its area is   cm2,

which is not equivalent to 6 cm2.

49. OPEN ENDED  Draw a right triangle that has a hypotenuse of  units.

SOLUTION:  Use the Pythagorean Theorem to select two side lengths for a and b with the given value of c.

 

50. WRITING IN MATH  Explain how to determine whether segments in three lengths could form a right triangle.

SOLUTION:  

From the converse of the Pythagorean Theorem, if a2 + b

2 = c

2 then a, b, and c are the lengths of the side of a right

triangle. So, check to see whether the square of the greatest number is equal to the sum of the squares of the other two numbers. Consider triangle with sides of 9, 12 and 15 and a triangle with sides of 7, 13 and 19. 

   

51. GEOMETRY  Find the missing length.

A  −17

B  −

C  

D  17

SOLUTION:  

The correct choice is C.

52. What is a solution of this equation?

F  0, 3 G  3 H  0 J  no solutions

SOLUTION:  

The correct choice is H.

53. SHORT RESPONSE  A plumber charges $40 for the first hour of each house call plus $8 for each additional half hour. If the plumber works for 4 hours, how much does he charge?

SOLUTION:  Let x = the total number of hours worked.

The plumber charges $88 for 4 hours of work.

54. Find the next term in the geometric sequence .

A  

B  

C   

D  

SOLUTION:  

The correct choice is B.

Solve each equation. Check your solution.

55. 

SOLUTION:  

Check.

56. 

SOLUTION:  

Check.

57. 

SOLUTION:  

Check.

58. 

SOLUTION:  

Check.

59. 

SOLUTION:  

Check.

60. 

SOLUTION:  

Check.

There is no real solution.

Simplify each expression.

61. 

SOLUTION:  

62. 

SOLUTION:  

63. 

SOLUTION:  

64. 

SOLUTION:  

65. 

SOLUTION:  

66. 

SOLUTION:  

Describe how the graph of each function is related to the graph of f (x) = x2.

67. g(x) = x2 − 8

SOLUTION:  

The graph of f (x) = x2 + c represents a vertical translation of the parent graph. The value of c is –8, and –8 < 0. If c

< 0, the graph of f (x) = x2 is translated  units down. Therefore, the graph of g(x) = x

2 – 8 is a translation of the

parent graph shifted down 8 units.

68. h(x) = x2

SOLUTION:  

The graph of f (x) = ax2 stretches or compresses the graph of f (x) = x

2 vertically. The value of a is , and 0 <  <

1. If 0 <  < 1, the graph of f (x) = x2 is compressed vertically. Therefore, the graph of h(x) = x

2 is the parent

graph compressed vertically.

69. h(x) = −x2 + 5

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is 5, and 5 > 0. If c > 0, the graph of f (x) = x2 is translated

 units up. Therefore, the graph of h(x) = −x2 + 5 is a translation of the parent graph shifted up 8 units and

reflected across the x-axis.

70. g(x) = (x + 10)2

SOLUTION:  

The graph of f (x) = (x – c)2 represents a horizontal translation of the parent graph. The value of c is –10, and –10 <

0. If c < 0, the graph of f (x) = (x – c)2

is translated  units left. Therefore, the graph of g(x) = (x + 10)2 is a

translation of the parent graph shifted left 10 units.

71. g(x) = −2x2

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = ax

2 stretches or

compresses the graph of f (x) = x2 vertically. The value of a is –2, and |–2| > 1. If  > 1, the graph of f (x) = x

2 is

stretched vertically. Therefore, the graph of g(x) = –2x2 is the parent graph reflected across the x-axis and stretched

vertically.

72. h(x) = −x2 −

SOLUTION:  

The graph of f (x) = –x2 reflects the graph of f (x) = x

2 across the x-axis. The graph of f (x) = x

2 + c represents a

vertical translation of the parent graph. The value of c is , and < 0. If c < 0, the graph of f (x) = x2 is

translated  units down. Therefore, the graph of h(x) = −x2 is a translation of the parent graph shifted down

 units and reflected across the x-axis.

73. ROCK CLIMBING  While rock climbing, Damaris launches a grappling hook from a height of 6 feet with an initialupward velocity of 56 feet per second. The hook just misses the stone ledge that she wants to scale. As it falls, the hook anchors on a ledge 30 feet above the ground. How long was the hook in the air?

SOLUTION:  

A half second after she throws the hook, it is 30 feet in the air. The hook continues up, then drops back down to the height of 30 feet 3 seconds after the throw. The hook was in the air for 3 seconds.

Find each product.74. (b + 8)(b + 2)

SOLUTION:  

75. (x − 4)(x − 9)

SOLUTION:  

76. (y + 4)(y − 8)

SOLUTION:  

77. (p + 2)(p − 10)

SOLUTION:  

78. (2w − 5)(w + 7)

SOLUTION:  

79. (8d + 3)(5d + 2)

SOLUTION:  

80. BUSINESS  The amount of money spent at West Outlet Mall continues to increase. The total T(x) in millions of

dollars can be estimated by the function T(x) = 12(1.12)x, where x is the number of years after it opened in 2005.

Find the amount of sales in 2015, 2016, and 2017.

SOLUTION:  

The sales for the mall in 2015 will be about $37.27 million; in 2016 will be about $41.74 million; and in 2017 will be about $46.75 million.

Solve each proportion.

81. 

SOLUTION:  

82. 

SOLUTION:  

83. 

SOLUTION:  

84. 

SOLUTION:  

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10-5 The Pythagorean Theorem