pyramid

A pyramid is a three-dimensional shape. Its base is a polygon and it has triangular faces which meet at a point above the base. This point is called the apex of the pyramid.

The formula for the volume of a pyramid is:

    \text {Volume} = \dfrac13 \times b \times h

In this formula b represents the area of the base and h represents the height of the pyramid (the smallest distance from the base to the apex).

An ordinary pyramid (e.g. an Egyptian pyramid) has a square base.

A pyramid with a triangular base is called a tetrahedron. The faces of a tetrahedron are all triangular in shape.

All pyramids have triangular-shaped faces, but the shape of the base can vary.