Problem 16: The extended of Newton line

by henderson, Jun 1, 2016, 6:18 PM

$$\bf\color{red}Problem \ 16 \ $$Let $(O)$ be the circumcircle of $ABCD$. Let the external bisectors of $\angle BAD, \angle ABC, \angle BCD$ and $\angle ADC$ intersect at $M,N,P,Q.$. Prove that the midpoints of $MP$, $NQ$ and $O$ are collinear.

http://i.imgur.com/1igZd3A.png


$\blacktriangleright$ Link to the problem
This post has been edited 6 times. Last edited by henderson, Sep 11, 2016, 7:53 PM
Newton line

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