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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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