Maybe you would have to experiment using 'sides' of the polyhedron's faces, the way she did here, in proving no polyhedron has seven edges:
http://plus.maths.org/content/os/issue43/features/kirk/proof
but as I could barely follow *that* one, that's all the 'help' I can offer :)
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until abi answers...
Maybe you would have to experiment using 'sides' of the polyhedron's faces, the way she did here, in proving no polyhedron has seven edges:
http://plus.maths.org/content/os/issue43/features/kirk/proof
but as I could barely follow *that* one, that's all the 'help' I can offer :)