Answer:
The slant height of the pyramid is 3√2 ft, or to the nearest tenth ft,
4.2 ft
Step-by-step explanation:
The equation for the volume of a pyramid of base area B and height h is
V = (1/3)·B·h. Here, V = 432 ft³, B = (12 ft)² and h (height of the pyramid) is unknown. First we find the height of this pyramid, and then the slant height.
V = 432 ft³ = (144 ft²)·h, so h = (432 ft³) / (144 ft²) = 3 ft.
Now to find the slant height of this pyramid: That height is the length of the hypotenuse of a right triangle whose base length is half of 12 ft, that is, the base length is 6 ft, and the height is 3 ft (as found above).
Then hyp² = (3 ft)(6 ft) = 18 ft², and the hyp (which is also the desired slant height) is hyp = √18, or √9√2, or 3√2 ft.
The slant height of the pyramid is 3√2 ft, or to the nearest tenth ft,
4.2 ft
