Question

The base of the pyramid is a square, with edges of 115 feet. The height of each lateral face is approximately 91.4 feet. How much glass was needed to construct the sides of the pyramid?

5,255.5 square feet
15,766.5 square feet
42,044 square feet
21,022 square feet

Answer 1

Check the picture below.

so each triangular face has a height of 91.4 and a base of 115, and there are four of them, now, we're only considering the "lateral area", that excludes the base.

$\stackrel{\textit{area of 4 triangles}}{4\left[ \cfrac{1}{2}(115)(91.4) \right]}~~\implies ~~ 21022$