The lateral area of a regular pyramid is L=1/2 P l, where P is the perimeter of the base and l is the slant height of the pyramid.
About 28 013.7 square yards
Practice makes perfect
A pyramid in Mexico City can be modeled by the following square pyramid with a height of h=20 yards and a base edge of s=165 yards.
We are asked to find the lateral area of the building. It's equal to L=1/2 P l, where P is the perimeter of the base, and l is the slant height of the pyramid. First, let's find l. We will use the Pythagorean Theorem for right △ ABC. Note that AB is half of the side length of the base. This tells us that AB= 1652=82.5 yards.
Therefore, the slant height is about 84.89 yards. Since the base of our pyramid is a square, its perimeter is P=4* 165= 660 yards. Now, let's find L by substituting values into the formula for the lateral area.
