Question

The surface area of a triangular pyramid is 305 squarei nches.The area of the base is 35 square inches. Each face has a base of 9 inches. What is the slant height?

Answer 1

305 = 35 + 3 * [( 9 * s) / 2] ; where s = the slant height ;
270 = 3 * [( 9 * s) / 2] ;
90 = ( 9 * s ) / 2 ;
180 = 9 * s ;
s = 20 inches.