Answer:
54 m^2
Explanation:
Area = 1/2 * base * height
You are missing height, but because you have the hypotenuse, you can use the Pythagorean Theorem to find it.
height^2 + (9m)^2 = (15m)^2
height = sqrt(225 m^2 - 81 m^2)
height = sqrt(144 m^2) = 12m
Area = 1/2 * 9m * 12m = 54 m^2