Pythagorean Theorem (8th Math)

The Pythagorean Theorem

The Pythagorean Theorem is used to find the unknown side measure in a right triangle. You may remember the Pythagorean Theorem from Geometry.

Poll

The formula for the Pythagorean Theorem is below. Does this formula seem familiar to you?  

 $a^2+b^2=c^2$  

• Yes!

• A little bit

• Not at all!

Poll

How do you feel about Pythagorean theorem at this point?

• Great, I could teach it to someone

• Good, I still have a few questions

• I am very confused and I don't no where to start

Parts of a Right Triangle

• Hypotenuse - Side across from (opposite) the right angle

• Legs - The other 2 sides

Hypothenuse

• The longest side of a right triangle

• The side of a right triangle that is opposite from the 90 degree angle

• When using the Pythagorean Theorem, the Hypotenuse is represented by the variable c

• This length is less than the sum of the length of the legs

Multiple Choice

Which side is the hypotenuse in this right triangle?

• 5

• 12

• 13

Multiple Choice

What is the hypothenuse of this right triangle?

• 13

• 12

• 5

Pythagorean Theorem

The area of the square whose side is the hypotenuse(diagonal) is equal to the sum of the areas of the squares on the other two sides.

 $a^2+b^2=c^2$  

Label your sides a, b, and c

• the hypothenuse c is the longest side

• c is the side of a right triangle that is opposite from the 90 degree angle

• a and b are the legs

Multiple Choice

Substitute your values to the theorem

• $a^2+6^2=8^2$

• $8^2+6^2=c^2$

• $8^2+b^2=6^2$

Solve for the missing length

You must take the square root to get the length side.

Multiple Choice

Solve the problem on your paper and type your answer in. #1 Find the Missing Side.

 $a^2+b^2=c^2$  

• c=18

• c=16

• c=17

• c=19

Multiple Choice

A triangle has legs that are 7 in and 24 in long. How long is the hypothenuse?

• 23

• 26

• 28

• 25

Label your sides a, b, and c

Type in chat what the side lengths are.

Multiple Choice

Substitute your values to the theorem

•  $a^2+12^2=20^2$ 

•  $20^2+12^2=c^2$ 

Multiple Choice

Solve the problem on your paper and type your answer in. #2 Find the Missing Side

• b=11

• b=12

• b=13

• b=14

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