A paperweight in the shape of a square pyramid has a side length of 8.2 inches. The slant height is 15.9 inches. What is the surface area of the paperweight?

The base of the pyramid is the side length squared

Base Area = (side length) (side length)

= (8.2) (8.2)

= 67.24

The slant length and side length is used to calculate the area of one slated face of the pyramid. Using the formula for a trangle (bh/2) we can find the area of one face

Face = bh/2

= 8.2 (15.9) / 2

= 130.38/2

= 65.19

As there are 4 faces, and one base the total area is the sum of 4 faces and the base area

A = 4F+BA

= 4 (65.19) + 67.24

= 260.76 + 67.24

= 328 in²