Y by Adventure10, Mango247
The convex hexagon ABCDEF is inscribed in a circle. Prove that the diagonals AD, BE and CF are concurrent if and only if
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I have proved the "only if" part using similar tringles and ratios and whatnot, but I'm struggling with the "if" implication. If someone could help then that would be great.

I have proved the "only if" part using similar tringles and ratios and whatnot, but I'm struggling with the "if" implication. If someone could help then that would be great.