pyramids

A pyramid is a polyhedron that is limited by a base and whose lateral faces are triangles with a common vertex called vertex of the pyramid.

The height of a pyramid is the distance between the vertex and the plane which contains the base.

A pyramid is regular when the base is regular and the vertex projects itself in the center of the polygon.

In a regular pyramid all the lateral edges have the same length and all the lateral faces are equal isosceles triangles. The height of these triangles is called apothem of the pyramid.

Development of a right pyramid and its area