Question

A square pyramid has a base with sides that are 12 cm long and a height of 9 cm. What is the surface area of the pyramid?

Answer 1

Check the picture below.

since the pyramid has 4 triangular faces and a square base, let's add their areas together and that'd be the area of the pyramid.

`\stackrel{\textit{\Large total area}}{\stackrel{base}{(12\cdot 12)}+\stackrel{4~triangles}{4\left[\cfrac{1}{2}(12)(6√(3)) \right]}}\implies 144 + 144√(3)~~\approx ~~393.42`