Euler's Theorem For Polyhedra

Euler's theorem for polyhedra demonstrates the constant relationship among the components of a given polyhedron:
the number of polygons+the number of vertices =the number of edges+2
P
+
V
=
E
+2
Take the cube for example:
P = 6, V = 8, E = 12
P + V = 6 + 8 = 14
E + 2 = 12 + 2 = 14