Polyhedrons

A polyhedron is a solid whose faces are polygons. It does not have any curved surfaces.

Examples:

• A polyhedron is convex when no part of its angles point towards the inside of the solid. In other words, it does not contain a hollow or cavity.
• A polyhedron is non-convex (concave) when at least one part of it angles points towards the inside of the solid. In other words, it contains at least one hollow or cavity.

Examples:

Convex	Non-convex

Connect different points of the solid with line segments to check if a polyhedron is convex or non-convex.

A polyhedron is non-convex if at least one line segment connecting two points lies outside the solid.

Examples:

Convex	Non-convex