Answer:
Pyramid is basically a 3D shape. Even though we have formulas to find surface area of pyramid with triangular base, the basic idea of finding surface is to add the areas of all the faces.
For any pyramid, if the shape of the base is equilateral triangle, then we will have three side walls. The shape of each side wall will be a triangle with equal area.
In the above pyramid, the base is an equilateral triangle with side length "a".
And each wall is a triangle with base "a" and height "h"
Let us find the area of each face separately.
Area of the base = (√3/4)a2
Area of each side wall = (1/2)ah
Area of all 3 side walls = 3 x (1/2)ah = (3/2)ah
Surface area of the above pyramid is = (√3/4)a2 + (3/2)ah
This is the formula to find surface area of a pyramid with equilateral triangle base.
Step-by-step explanation: