Answer:
12 in.
Explanation:
Leg = a = 9 in.
Leg = b
Hypotenuse (side opposite of the right angle) = c = 15 in.
Use the pythagorean theorem to find the missing side length


Simplify

Subtract 81 from both sides of the equation

Find the square root of 144
b =

b = 12
12 in
Hope this helps :)