Problem 42: IMO Shortlist 2012 , G2

by henderson, Jul 23, 2016, 3:15 PM

$$\color{red}\bf{Problem \ 42}$$Let $ABCD$ be a cyclic quadrilateral whose diagonals $AC$ and $BD$ meet at $E.$ The extensions of the sides $AD$ and $BC$ beyond $A$ and $B$ meet at $F.$ Let $G$ be the point such that $ECGD$ is a parallelogram, and let $H$ be the image of $E$ under reflection in $AD.$ Prove that $D, H, F, G$ are concyclic. $($ My solution $)$
This post has been edited 3 times. Last edited by henderson, Jan 13, 2017, 10:31 AM
geometry
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U still haven't written it...

by L567, Jan 2, 2021, 6:04 PM

"Do not worry too much about your difficulties in mathematics, I can assure you that mine are still greater." - Albert Einstein

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henderson
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