Respuesta :

mgalbearth

Answer:

9

Step-by-step explanation:

BenDaChickenMaster
So Pythagorean Theorem is a^2 + b^2 = c^2. A is x, b is 12 because the opposite side is 12, and c is 15. Then substitute them in and multiply by themselves. X^2 plus 144 is 225. Subtract from both sides. X^2 is 81. So them un-square 81. X is 9.