Chapter 6.3, Problem 35MS

Here we celebrate the power of algebra as a powerful way of finding unknown quantities by naming them, of expressing infinitely many relationships and connect ions clearly and succinctly, and of uncovering pattern and structure.

Planar puzzle. Someone chalked a planar graph on the sidewalk in front of the student union. It has twice as many edges as vertices and twelve fewer regions than three times the number of vertices. How many vertices does the graph have? Will the chalker be called to the Dean’s Office?