Answer:
12.4
Explanation:
We have a right triangle, so we can use the Pythagorean theorem
a^2 + b^2 = c^2 where a and b are the legs and c is the hypotenuse
3^2 + 12^2 = h^2
9+144= h^2
153 = h^2
Take the square root of each side
sqrt(153) = sqrt(h^2)
12.36931688 =h
Rounding to the nearest tenth
12.4 =h