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Let $G$ a planar graph and $e$ an edge of $G$. Describe a way (method) to give a planar embedding of the graph such that $e$ is in the outer face of the graph.

Any help?

Thank you!

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Draw the graph on a sphere. Declare a point next to the chosen edge to be the north pole and project the sphere stereographically to a plane.

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    It would help, passenger, if you would indicate just exactly what part(s) of Henning's answer require more explanation.2012-02-12