Question

A square base of a pyramid has the dimensions 5 yards

by 5 yards. The height of one of the triangular faces is 12
yards. How can you find the surface area of the pyramid?

Answer 1

Sample Response:

First, draw and label a net of the pyramid. The triangular faces have a base of 5 yards and a height of 12 yards. Find the area of each of the faces. The square base has an area of 25 yd2. Each of the triangular faces has an area of 30 yd2. Add the areas together to find the surface area: 25 + 30 + 30 + 30 + 30 = 145 yd2.

Answer 2

145 yd²

Explanation:

There will be dour triangular faces. For a triangle, area is given as

A=½bh where b is base and h is height. The base will be 5 yards and h is 12 yards hence for one triangular face, area will be ½*5*12=30 yd²

Since they are four similar triangles, area of triangular faces will be 30*4=120 yd²

The surface area of a square base is given by

A=a*a=a² where a is the dimension of one side. Given that the meaurement is 5 yards then A=5²=25 yd²

Total area will be the sum of triangular and square faces hence 120+25=145 yd²