Created by G. Antidormi 2003

The Pythagorean Theorem

Created by G. Antidormi 2003

What is the Pythagorean Theorem used for?

• to find the length of a missing side in a right triangle

5

4

n

Created by G. Antidormi 2003

Pythagorean Theorem Formula

• a2 + b2 = c2

c represents the hypotenuse

a and b represent the legs

Created by G. Antidormi 2003

hypotenuse

leg

leg

a

b

c

Created by G. Antidormi 2003

Important bits of information

• The Pythagorean Theorem can only be used on a right triangle.

• The legs are always the sides adjacent (next to) the 90 degree angle.

• It does not matter which leg is a and which leg is b.

• c is always the hypotenuse (the slant)

Created by G. Antidormi 2003

What is the length of the hypotenuse in the triangle below?

2

4

ha2 + b2 = c2

Created by G. Antidormi 2003

Plug in the value for each variable in the formula.

Created by G. Antidormi 2003

What is the length of the hypotenuse in the triangle below?

2

4

h

a2 + b2 = c2

22 + 42 = h2

4 + 16 = h2

20 = h2

Created by G. Antidormi 2003

What is the length of the hypotenuse in the triangle below?

2

4

ha2 + b2 = c2

22 + 42 = h2

4 + 16 = h2

20 = h2

20 = h

4.47~~ h

Created by G. Antidormi 2003

Try this one . . .

Find the hypotenuse of the right triangle below?

64

h

Created by G. Antidormi 2003

Find the hypotenuse of the right triangle below?

6

4

h

a2 + b2 = c2

42 + 62 = h2

16 + 36 = h2

52 = h2

52 = h

7.21 = h

Created by G. Antidormi 2003

What is the length of the missing leg in the triangle below?

3

x

5a2 + b2 = c2

Try this one . . .

Created by G. Antidormi 2003

Find the hypotenuse of the right triangle below?

53

x

a2 + b2 = c2

32 + x2 = 52

9 + x2 = 25

x2 = 16 16x=

x = 4

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