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FHS Chapter 5 2

Review: Right Triangle

• What are a and b called?

the legs

• What is c called?

the hypotenuse a

b

c

• What is a right triangle?

A triangle with a right angle

FHS Chapter 5 3

The Pythagorean Theorem

The Pythagorean Theorem states that in a right triangle, the sum of the squares of the lengths of the legs is equal to the square of the length of the hypotenuse.

a2 + b2 = c2 a

b

c

FHS Chapter 5 4

The Pythagorean Theorem can be used to find missing parts of a right triangle.If the one leg is 3 inches and the hypotenuse

is 5 in., we can find the other leg.

a2 + b2 = c2

32 + b2 = 52

9 + b2 = 25 b2 = 16

b = 4 in.

5 in.

3 in.

b

FHS Chapter 5 5

Find the hypotenuse if given the two legs of 5 ft and 12 ft.

a2 + b2 = c2 → 52 + 122 = c2

25 + 144 = c2 → c2 = 169 c = 13 in.Can these numbers be the sides of a

right triangle? 4, 5 and 6Square all three numbers. Add the two smallest

ones together. Is this the same as the largest square?

a2 = 16 b2 = 25 c2 = 36 Is 16 + 25 = 36?