Question

A regular octagonal pyramid has a base edge of 3m and a lateral area of 60m^2. Find its slant height.

Answer 1

Octagon = 8-side polygon

Find area of 1 triangle:
Area of one side triangle = 60 ÷ 8 = 7.5 m²

Given area and length, find height:
Area of each triangle = 7.6 m²
Length of each triangle = 3m

Area = 1/2 x base x height
7.5 = 1/2 x 3 x height
Heigth = 5m

Answer: Slanted Height = 5 m