Question

In a pentagonal pyramid you have 6 vertices and 6 faces. Find the number of edges using Euler’s theorem

Answer 1

The number of edges is 10

Explanation:

we know that

The Euler's formula state that, the number of vertices, minus the number of edges, plus the number of faces, is equal to two

`V - E + F = 2`

we have

`V=6\\F=6\\E=?`

substitute the values

`6 - E + 6 = 2`

solve for E

`- E + 12 = 2`

`E=12-2\\E=10`