Euler's formula
Faces + Vertices - Edges = 2
Substituting with
• Faces = 7
,
• Vertcies = 5
we get:
7 + 5 - Edges = 2
12 - Edges = 2
Subtracting 12 at both sides of the equation:
12 - Edges - 12 = 2 - 12
-Edges = -10
Dividing by -1 at both sides of the equation:
