A pyramid is a solid formed by a polygonal base whose vertices join to the same point - not coplanar with the base - called the apex of the pyramid. A pyramid with a quadrilateral base is also called quadrilateral, square if the base is square. In addition to the base, the pyramid has triangular faces said to be lateral; the edges that join the base and the apex are also lateral.
A quadrilateral pyramid has 5 vertices, 8 edges and 5 faces. You can check the Euler's formula for this solid:
Press right mouse button down to drag the pyramid
Copyright © 1996-2018 Alexander Bogomolny