Let G be a 4 regular connected planar graph (with a planar embedding), where all faces are either degree 3 or degree 4.
Then determine the number of faces of degree 3.
Also, now suppose that every vertex in G is incident with 1 face of degree 3, and 3 faces of degree 4. Determine the number of vertices, edges, and faces of degree 4 in G.
I think this question is solved using Euler's formula, $v-e+f=2$, but I'm not entirely sure how to use that to solve the problem. I know that $e=2v$, but what else can be figured out from the question? Thank you in advance!