Answer:
15
Step-by-step 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
9^2 + 12 ^2 = c^2
81+144= c^2
225 = c^2
Take the square root of each side
sqrt(225) = sqrt(c^2)
15 =c
