Answer:
x=15
Explanation:
Since this is a right triangle, we can use the Pythagorean theorem
a^2+b^2 = c^2 where a and b are the legs and c is the hypotenuse
The legs and x and 20 and the hypotenuse is 25
20 ^2+x^2 = 25^2
400 + x^2 = 625
Subtract 400 from each side
x^2 = 625-400
x^2 = 225
Take the square root of each side
sqrt(x^2) = sqrt(225)
x = 15