Definition §

Planar Graph

A Planar garph is a graph where none of the edges cross (Intercept) Planar Graphs can be formed into a 3d shape. (e.g. could be made physically)

Eulers Formula §

In any Planar Graph the following is true. Where: = Vertices = Faces = Edges

Example

If Planar; the following is true: 4+6-4=2