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MathNet 2016-part-04 — 184 problems (EN–VI) Question 133

Math Olympiad Vault · MathNet 2016-part-04 — 184 problems (EN–VI)

Question 133

Let $L$ be a point on the side $AC$ of a triangle $ABC$ such that $BL$ is the bisector of the angle $ABC$. Let $M$ be a point on the segment $CL$. The tangent through $B$ to the circumcircle $\Omega$ of $ABC$ meets the ray $CA$ at $P$. Tangents through $B$ and $M$ to the circumcircle $\Gamma$ of $\triangle BLM$ meet at $Q$. Prove that $PQ \parallel BL$.
(A. Kuznetsov)