If the hypotenuse of a triangle is 30 inches and one of the legs is 10 in, how long is the other leg?

1 Answer
Mar 17, 2018

The leg is 20sqrt2

Explanation:

We'll solve this using the Pythagorean Theorem.

a^2 + b^2 = c^2
where a and b are the length of the legs , and c is the length of the hypotenuse.

Let's plug in the values in the question:
a^2 + b^2 = c^2
10^2 + b^2 = 30^2
100 + b^2 =900
b^2 = 800
b=sqrt800

Now simplify sqrt800 to find the exact length:
sqrt800=sqrt(2×2^2×(2×5)^2)=2×2×5×sqrt2=20sqrt2

The length of the side is 20sqrt2