I need the answer because i been trying to figure this out for 20 minutes

Answer:
sqrt (65) = 8.062 units = x
Step-by-step explanation:
use Pythagorean theorem for a right triangle
a ^2 + b^2 = c^2 where a and b are the legs and c is the hypotenuse
4^2 + x^2 = 9^2
x^2 = 9^2 - 4^2
x^2 = 65
x = sqrt 65