Answer: x=12
Explanation:
The Pythagorean theorem is a²+b²=c². A and b are the legs, and c is the hypotenuse. Since we are only given the length of a leg and hypotenuse, we fill in what we have and solve for a.
a²+16²=20² [exponent]
a²+256=400 [subtract both sides by 256]
a²=144 [square root both sides]
a=12
Now, we know the missing leg, x=12.