Answer:
9
Explanation:
Pythagorean theorem is a^2 + b^2 = c^2.
In this case, a = 12, c = 15, and we do not know the value of "b."
Let's solve by plugging the values in!
12^2 + b^2 = 15^2
144 + b^2 = 225
Subtract 144 on both sides:
b^2 = 81
b = sqrt 81
b = 9