Hi

I have this graph

now i should check if this graph can be planar.

v - number of vertices

e - number of edges

f - number of faces

So it's hold the theorem "Ifv ≥ 3 thene≤v = 9, e = 153v − 6 "

15 ≤ 21

and should hold v - e + f = 2 from here f = 2 - v + e = 2 - 9 + 15 = 8

so f = 8 now my question is how to easily count faces (regions bounded by edges, including the outer, infinitely large region) of the graph??

thanks