Answer:
10.8 ft
Explanation:
The height from the base can be found from the formula for the volume. Fill in the given information and solve for the height.
V = (1/3)Bh = (1/3)s²·h
432 ft³ = (1/3)(12 ft)²·h . . . . . fill in side length and volume
h = 432 ft³/(48 ft²) = 9 ft . . . divide by the coefficient of h
The slant height is the hypotenuse of a right triangle with this height as one leg and half the side length as the other leg.
slant height = √((9 ft)² +(12 ft/2)²) = √(117 ft²) = 3√13 ft
slant height ≈ 18.817 ft ≈ 18.8 ft