An equilateral triangular pyramid has a slant height of 8.3 inches. The triangular base has a perimeter of 4.8 inches and an area of 1.1 square inches. Find the surface area of the pyramid.

1 answer

so each side of the base has length 4.8/3 = 1.6
The lateral area is 3 triangles, each with base 1.6 and height 8.3
A = 3 * (1.6*8.3)/2 = ____

Sorry, but an equilateral triangle of perimeter 4.8 has an area of
1.6^2/4 * sqrt(3) = 0.55
so how come yours is double that?