# Using the Pythagorean Theorem to find a Missing Hypotenuse - Concept

###### Explanation

The hypotenuse of a right triangle is the side that is opposite of its right angle. Sometimes we have problems that ask us to find the missing hypotenuse of a right triangle. We can use the Pythagorean theorem to **find the hypotenuse**, but only if we know the length measure of the two legs.

###### Transcript

The Pythagorean theorem says that if

you have a right triangle where you

know your two legs and a hypotenuse where

the legs are the sides adjacent

to your right angle and the hypotenuse

is the side that is opposite the

right angle, there exists this relationship

that if you take one of the

legs N squared and if you add it to the

other leg, N squared, that's going

to equal the square of the hypotenuse.

So if you're trying to solve for one of

these variables, you're going to need

two of them.

And the easiest problem that you're going

to see using the Pythagorean theorem

is one where you know your two legs and

you're trying to find your hypotenuse.

The reason why this is the easiest is because

all you have to do is substitute

in and then you can square it equal

C squared and then you're going to

have 13 equals C squared and you can

take the square root and C equals

the square root of 13.

So I didn't have to do any

manipulation there.

All I had to do was plug in my two legs

and then solve for my hypotenuse.