Question

sarah is designing a triangular pyramid made of all glass to go on top of a building. all of the faces of the pyramid have a height of 17 feet and a base of 20 feet.
note: figure is not drawn to scale.
how much glass is needed?
a. 680 sq ft
b. 340 sq ft
c. 1,360 sq ft
d. 2,040 sq ft

Explanation:

Step1: Calculate the area of one triangular face

The formula for the area of a triangle is \(A=\frac{1}{2}\times base\times height\). Given \(base = 20\) feet and \(height=17\) feet.
\(A=\frac{1}{2}\times20\times17= 170\) square feet.

Step2: Find the total surface area (since there are 4 triangular faces)

Multiply the area of one face by 4. \(Total\ area=4\times170 = 680\) square feet.

Answer:

A. 680 sq ft