Question

Find the surface area of the equilateral triangular pyramid.

Answer 1

We know that
[surface area of the triangular pyramid]=area of the base+3*[area of lateral triangles]
area of the base=12*8/2-----> 48 cm²

area of one lateral triangle=12*10/2-----> 60 cm²
[surface area of the triangular pyramid]=48+3*[60]-----> 228 cm²

the answer is the option 
B) 228 cm2