can someone please help me find the answer to the following?

Can Someone Please Help Me Find The Answer To The Following class=

Answer :

Using the Euler formula, we have:

F + V = E + 2 (F: faces, E:edges, V:vertices)

F + 12 = 18 + 2 (Replacing)

F + 12 = 20 (Adding)

F= 8 (Subtracting 12 from both sides of the equation)

The answer is 8.