Let $G$ be a connected graph in which every pair of edges has an endpoint in common. Show that $G$ is either a star or the complete graph $K(3)$.
Discrete Mathematics, Graph Theory
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graph-theory
discrete-mathematics
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0This is not true for non-simple graphs. – 2012-12-01
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4Does it have any relation to question 4 on this ongoing assignment [here](http://www.math.mcgill.ca/louigi/courses/20122013/math240/a5.pdf)? – 2012-12-01
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2Indeed Douglas, two other questions on that assignment were asked earlier today, all by unregistered user(s). – 2012-12-01
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0[Another one](http://math.stackexchange.com/questions/248872/discrete-mathematics-more-graph-theory) has just been asked. – 2012-12-01