Find the total surface area of a square pyramid with a base length of 18 and height of 12

2 answers

What are the units that go with your numbers? Meters? Miles? Whetever?

The base area is 18x18 whatevers.

You need the lateral height h of the four triangular sides, measured from the midpoint of one of the base sides to the apex. You can get that using the Pythagorean theorem.

h^2 = 9^2 + 12^2
h = 15

One Side area = (1/2)bh = (1/2)*12*15 = 90

Add up the five side areas for the total.
the surface area of a prism is 120 sqaure cm and the area of each base is 32 square cm find the lateral area of the prism.