Pyramid

A pyramid has a base that is a polygon. The name of the pyramid comes from the base. Below is a square from which we can construct a square based pyramid.

A pyramid can be constructed by drawing lines from each corner of the square to a point above the plane of the square. In the picture below, we are looking down on the dot and the square from above.

It is easier to visualise the point above the square if we view the square and point more from the side

Drawing lines to the point from each corner of the square gives a representation of a pyramid

Each face of the pyramid is a triangle. There is one triangle for each side of the base.

These are the 2D shapes that make up the pyramid

The surface area of the pyramid is calculated by adding up the areas of all of the 2D shapes that make up the pyramid. For a square base that has sides of 5cm and triangles that are 10cm from the centre of their base to the apex, the area is

To be a pyramid

• the sides are triangles that meet at a point above the base
• the base is a polygon