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MathNet 2018-part-02 — 181 problems (EN–VI) Question 180

Math Olympiad Vault · MathNet 2018-part-02 — 181 problems (EN–VI)

Question 180

Let $ABC$ be a triangle. Denote by $L, M, N$ the midpoints of $[BC]$, $[CA]$ and $[AB]$. Let $(d)$ be the tangent at $A$ to the circumcircle of $ABC$. The line $(LM)$ meets $(d)$ at $P$, and the line $(LN)$ meets $(d)$ at $Q$. Show that $(CP)$ and $(BQ)$ are parallel.