Chi is building a sandcastle in the shape of a triangular pyramid. The area of the base is 7 square feet. Each side of the base has a length of 4 ft and the height of each face is 2 feet. What is the surface area?
Find the area of one of the triangular sides, so 4×2=8. multiply that by 3 because there are three triangular sides in a triangular pyramid, so 8×3=24. add that with the area of the base, so 7+24=31