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REVISION WITH ANSWERS – PLEASE REVISE
Algebra 1 Lesson 1.1 Variables and Expressions
Question 1:
Determine whichexpression containsone∨more variables .
A. -7
B. 5y2
C. π
D. 64
Question 2
Write an algebraic expression for the verbal expression.
Three added ¿twice anumber
Solution :2x+3∨3+2x
Question 3
the|expression
34
Solution :34=3×3×3×3=81
Question 4
Write averbal expression for thealgebraic expression
3 s2−5 t
Solution :The product of 5∧t , subtracted ¿ the product of 3∧the squareof s .
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Question 5:
Acar rental company chargesdaily a flat rate of 100dirhams∧an additional7dirhams
per kilometer k .Write analgrebraic expressionthat represents the totaldaily cost of renting
acar ¿ this company .
Solution :7k+100∨100+7k
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Algebra 1 lesson 1-2: Solving Equations by Adding or Subtracting
Question 1:
Determine if the given valueis a solution¿ the equation
m−5=−8
A. 5
B. 3
C. -3
D. -5
Question 2:
Solvethe equation .Then ˇyour solution.
11+x=13
Solution :
11+x=13
11+x+(−11)=13+(−11)
x=2
:̌
11+x=13
11+2=13
13=13✓
The solutionis2.
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Question 3:
If y−9=16 ,what is the value of y−6?
Solution :
y−9=3
y−9+9=3+9
y=12
So , y−6=12−6
y−6=6
Question 4:
Solvethe equation .Then ˇyour solution.
x− 53=−1
2
Solution :
x−53+ 5
3=−1
2+ 5
3
x=−12
+ 53=−3
6+10
6∨7
6
So ,x=76
:̌
76−5
3=−1
2
76−10
6=−1
2
−36
=−12
−12
=−12✓
The solutionis 76
Question 5:
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Write an equation for the problem. Then, solve the equation and check the solution.
The∑ of anumber∧−13is−28.What isthe number ?
Solution
Let x represent the number .
x+(−13 )=−28
x+(−13 )+13=−28+13
x=−15
:̌
−15+(−13 )=−28
−28=−28✓
The solutionis−15.
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Algebra 1 lesson 1-3: Solving Equations by Multiplying or Dividing
Question 1:
If 8 t=20 ,what isthe value of 16 t ?
A. 40
B. 30
C. 20
D. 10
Question 2:
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Solvethe equation .Then ˇyour solution.
35f=−18
Solution :
35f=−18
35f ×( 5
3 )=−18×( 53 )
f=−30
:̌
35f=−18
35(−30)=−18
−18=−18✓
The solutionis−30.
Question 3:
Solvethe equation .Then ˇyour solution.
0.36 x=9.135
Solution :
0.36 x0.36
=9.1350.36
x=2038
:̌
0.36 x=9.135
0.36×( 2038 )=9.135
9.135=9.135✓
Question 4:
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Solvethe equation .Then ˇyour solution.
− y5
=−35
Solution :
− y5×(−5)=−35×(−5)
y=175
:̌
− y5
=−35
−1755
=−35
−35=−35✓
The solutionis175
Question 5:
¿1993 , theworldrecord for thelargest ¿doughnut was established .Thedoughnut weighed1.5 tons∧¿hadacircumference of 50 feet .Using
the formula for the circumference of the C̊=πd , find the diameterof that doughnut .
Solution
C=πd
50=πd
50π
=πdπ
d=50πfeet
:̌
C=πd
50=π × 50π
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50=50✓
So ,the diameter was 50πfeet .
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Algebra 1 lesson 1-4: Solving Two-Step and Multi-Step Equations
Question 1:
Determineif the given valueis a solution¿ the given equation
−4 y−9=3
A. -3
B. -4
C. 3
D. 4
Question 2:
Solvethe equation .Then ˇyour solution.
−10 x+2=−18
Solution :
−10 x+2=−18
−10 x+2−2=−18−2
−10 x=−20
−10x−10
=−20−10
x=2
:̌
−10 x+2=−18
−10(2)+2=−18
−20+2=−18
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−18=−18✓
The solutionis2.
Question 3:
Solvethe equation .Then ˇyour solution.
−17=4 ( p−5)
Solution :
−17=4 ( p−5)
−17=4 p−20
−17+20=4 p−20+20
3=4 p
34=4 p
4
p=34∨p=0.75
:̌
−17=4 ( p−5)
−17=4∗( 34−5)
−17=4∗(−174 )
−17=−17✓
The solutionis 34.
Question 4:
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The sum of 3 times a number and 5 is 17. Find the number.
Solution :
Let x be the number .
3 x+5=17
3 x+5−5=17−5
3 x=12
3x3
=123
x=4
:̌
3(4)+5=17
12+5=17
17=17✓
The solutionis 4.So , the number is4.
Question 5:
Fatimawants¿buy adress that costs600dirhams . Shehas150dirhams∈her savings
¿ shereceives anallowance of 75dirhamseveryweek .Set up anequation¿determine
the number of weeks she needs¿ save her allowancemoney∈order ¿haveenough
money for the dress .
Solution :
Let x be the number of weeks Fatimaneeds ¿ save her allowancemoney .
150+75 x=600
150+75 x−150=600−150
150+75 x=600
75 x=450
75x75
=45075
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x=6
:̌
150+75 x=600
150+75(6)=600
600=600✓
The solutionis6. So ,Fatimaneeds ¿ save her allowancemoney for 6weeks .
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Algebra 1 Lesson 1-5 Solving Equations with Variables on Both Sides
Question 1:
Determine if the given valueis a solution¿ the given equation
8 t=4 t+16
A. -4
B. -3
C. 3
D. 4
Question 2
Solvethe equation .Then ˇyour solution.
5 ( x+6 )=2( x+3)
Solution :
5 ( x+6 )=2( x+3)
5 x+30=2 x+6
5 x+30−30=2x+6−30
5 x=2 x−24
5 x=2 x−24
5 x−2 x=2x−2x−24
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3 x=−24
3x3
=−243
x=−8
:̌
5 (−8+6 )=2(−8+3)
5(−2)=2(−5)
−10=−10✓
The solution is−8.
Question 3
Solvethe equation .Then ˇyour solution.
4 x+3=2(2 x+1)
Solution :
4 x+3=2(2 x+1)
4 x+3=4 x+2
4 x+3−4 x=4 x+2−4 x
3=2
No solution!
Question 4
Solvethe equation .Then ˇyour solution.
−3 ( x−2 )+4=5 ( x+2 )−8x
Solution :
−3 x+6+4=5 x+10−8x
−3 x+10=−3 x+10
−3 x+10+3 x=−3 x+10+3 x
10=10
Thereare infinitelymany solutions!
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Question 5:
The triangles shown have the same perimeter. What is the value of x?
Solution :
3 ( x+2 )=2 (3x−1 )+ x
3 x+6=6 x−2+ x
3 x+6=7 x−2
3 x+6−6=7 x−2−6
3 x=7 x−8
3 x−7 x=7 x−8−7 x
−4 x=−8
−4 x−4
=−8−4
x=2
:̌
3 (2+2 )=2 (3(2)−1 )+2
3 (4 )=2 (6−1 )+2
12=2 (5 )+2
12=12✓
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Algebra 1 Lesson 1-6 Solving for a variable
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Question 1:
Which equationis the result of Solving9+3 x=2 y for x?
A.9+3 y
2=x
B.23y−9=x
C. x=23y−3
D. x=2 y−3
Question 2:
Solve for the indicated variable
a¿ y=mx+b for x
y−b=mx
x= y−bm
b) PV=nRT for T
T=PVnR
c) A=12bh for b
bh=2 A
b=2Ah
Question 3:
The formula for a Fahrenheit temperature in terms of degree – Celsius is
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F=95C+32Solve for C
F−32=95C
9C=5 (F−32 )
C=59(F−32)
Question 4:
In your own words, explain how to solve a literal equation for one of the variables
Use inverse operations to isolate the indicated variable on one side of the equation. Be sure the variable is the only expression on one side of the equation and does not appear on the other side
Question 5:
Solve for the indicated variable
v2=u2+2as for s
v2−u2=2as
s= v2−u2
2a
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Algebra 1 Lesson 1-7 Solving absolute value equations
Question 1:
forwhichof the followingis n=−3asolution ?
A. |n−1|=2
B. |n+2|=−1
C. |n−2|=1
D. |n+1|=2
Question 2:
Solve each equation
a¿|2 x−4|=22
2 x−4=±22
2 x−4=22∨2x−4=−22
2 x=26∨2x=−18
x=13∨x=−9
b) |x−3|+14=5
|x−3|=−9 No solution
Question 3:
Is there a value of a for which the equation |x−a|=1 has exactly one solution? Explain
No, no matter what value of a is chosen, there will always be two solutions a+1 and a-1
Question 4:
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The perimeter of a rectangle is 100 inches. The length of the rectangle is |2 x−4| inches and the width is x inches. What are the possible values of x?
P=2 L+2W
100=2|2 x−4|+2 x
50=|2x−4|+x
|2 x−4|=50−x
2 x−4=50−x∨2 x−4=−50+x
3 x=54∨x=−46 rejected
x=18
Question 5:
A thermostat is set so that the temperature in a laboratory freezer stays within 2.5 ° F of 2 °F write and solve an absolute value equation to find the maximum and minimum temperatures in the freezer
|x−2|=2.5
x−2=2.5∨x−2=−2.5
x=4.5° F∨x=−0.5 ° F
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Algebra 1 Lesson 1-8 Rates, Ratios and proportions
Question 1:
Ali walksat a speed of 4miles per hour .Hewalks for 20minutes∈a straight line at this rate .approximatly what distancedoes Ali walk ?
A. 0.06miles
B. 1.3miles
C. 5miles
D. 80miles
Question 2:
Solve each proportion
a)x−1
3= x+1
55 x−5=3x+32 x=8x=4
b)3x+5
14= x
39 x+15=14 x5 x=15x=3
c)1x= 1
6 x−16 x−1= x5 x=1
x=15
Question 3:
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The ratio of faculty members to students at a college is 1:15 there are 675 students. How many faculty members are there?
Let x be the number of faculty members
115
= x675
15 x=675
x=45
There are 45 faculty members
Question 4:
On a certain day, the exchange rate was 60 U.S. dollars for 50 euro. How many U.S.dollars were 70 euro worth that day.
$60→50euro
$ x→70euro
50 x=60 (70 )
x=60(70)50
=$ 84
Question 5:
Give three Examples of proportions, how do you know they are proportions?
12=3
6
14= 5
20
37= 6
14
They are proportions because the cross products are equal
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Algebra 1 Lesson 1-9 Applications of proportions
Question 1:
Abeachball holds 800 cubic inchesof air . Another beachball hasa radius that is halfthat of thelarger ball . Howmuchair does the smaller ball hold?
A. 400 cubicinches
B. 200 cubic inches
C. 100 cubic inches
D. 80cubic inches
Question2:
A triangle has side lengths of 5 inches, 12 inches and 15 inches. Every dimension is
multiplied by 15 to form a new triangle. How is the ratio of the perimeters related to the
ratio of the corresponding sides?
Perimeter of the original triangle = 5+12+15=32inches
The new triangle has side lengths 1,2.4 3
Perimeter of the new triangle = 15(5+12+15)=6.4 inches
ratios of perimeters= 326.4
ratios of corresponding sides=51= 12
2.4=15
3= 32
6.4
The ratio of the perimeters is equal to the ratio of the corresponding side lengths
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Question3:
Ahmedis 5 feet tall∧casts a shadow3.5 feet long . At the same time , the flagpole
outside his school casts a shadow 14 feet long .write∧solve a proportion ¿ find theheight
of the flagpole
Let h be the height of the flagpole
5h=3.5
14
3.5h=70
h= 703.5
=20 feet
Question4:
A rectangle has length 5 cm and width 3 cm. A similar rectangle has length 7.25 cm what is the width of this rectangle
Let x be the width of the rectangle
57.25
=3x
21.75=5x
x=21.755
=4.35
Question5:
At Pizza Palace, a pizza with diameter of 8 inches cost $ 6. The restaurant manager says that a 16 inch pizza should be priced at $ 12 because it is twice as large. Do you agree?
No, a 16 inch pizza actually has 4 times the area so the cost should be 4 times as much
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Algebra 1 Lesson 1-10 Precision and accuracy
Question 1:
Themassof crystal is0.9728gramswhat is themass of the crystal ¿ the nearestmilligram
A. 1milligram
B. 9.73milligram
C. 973milligram
D. 972.8milligram
Question 2:
Round each measurement to the specified precision
a) 5456.3 mi to the nearest mile : 5456 mi b) 3.627 m to the nearest hundredth of meter : 3.63 m c) 119.8 ft to the nearest ten feet : 120 feet d) 62.301 cg to the nearest tenth of a centigram : 62.3 cg
Question 3:
Choose the more precise measurement in each pair
a) 16.270 Liters , 16453.2mlb) 437 cm , 437 mmc) 33mg , 0.033 g neitherd) 67 min , 1.1 h
Question 4:
Rewrite each specified tolerance as a percent
a) 25in ±0.25∈¿ : 25∈±1%b) 240 ft ±12 ft: 240 ft ±5 %
Question 5:
Write the possible range of each measurement. Round to the nearest hundredth
a¿50m±4 %: 48.00−52.00m
b¿90 ° F ±15 % :76.50F−103.50 F
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