You're now a square based pyramid with 4 triangular faces and a square face for your bottom. You can get pyramids with different shaped bases. Triangles, pentagons, hexagons, any shape.

The square-based pyramid, a shape which usually has four sides, is the most famous one at the Giza pyramid site. However researchers actually claim there are eight sides to it, making it an ...

A pyramid with a square base is a square-based pyramid. Image caption, 3D shapes that are non-polyhedral include cylinders, cones, and spheres. At least one face is not a polygon. At least one ...