Question

Andy is building a square pyramid out of cardboard. He wants the edges of the base to measure 3 in. and the sides to have a slant height of 5 in. How much cardboard will Andy need for the project?​

Answer 1

Check the picture below.

so the area of the pyramid is really just the area of a 3x3 square with four triangles with a base of 3 and a height of 5.

`\stackrel{ \textit{\LARGE Areas} }{\stackrel{ square }{(3)(3)}~~ + ~~\stackrel{ \textit{four triangles} }{4\left[\cfrac{1}{2}(\underset{b}{3})(\underset{h}{5}) \right]}}\implies 9+30\implies \text{\LARGE 39}~in^2\textit{ for the cardboard}`