# Pythagorean Theorem

In this video, we are going to look at how to find a missing side length of a right triangle by using the Pythagorean Theorem.

Pythagorean Theorem
$a^2+b^2=c^2$
where a and b are lengths of legs of the right triangle,
and c is the length of the hypotenuse.

For example:
To solve the following equation:
$a^2+b^2=c^2$

Substitute the variables where 3 replaces a and 4 replaces b
$3^2+4^2=x^2$

Solve for $3^2$ and $4^2$
$9+16=x^2$

Add the 9 and the 16 together, leaving us with:
$25=x^2$

Find the square roots on both sides
$\sqrt{25}=\sqrt{x^2}$

Leaving us with:
$5=x$
So the hypotenuse equals to 5

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