(Planar graph) A planar graph is a graph that can be drawn
Chapter 23, Problem 23.8(choose chapter or problem)
(Planar graph) A planar graph is a graph that can be drawn on a sheet of paper so that no two edges cross. Show that the complete graph K4 with four vertices is planar. The complete graph K5 with five vertices is not planar. Make this plausible by attempting to draw K5 so that no edges cross. Interpret the result in terms of a net of roads between five cities.
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