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USAJMO 2011 Question 5

USAJMO · USAJMO 2011

Question 5

Points $A,B,C,D,E$ lie on a circle $\omega$ and $P$ lies outside it. Lines $PB,PD$ are tangent to $\omega$; $P,A,C$ are collinear; and $DE\parallel AC$. Prove that $BE$ bisects the segment $AC$.

Proposed by Zuming Feng (credit in the supplied notes).