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MathNet 2011 Question 95

Math Olympiad Vault · MathNet 2011

Question 95

Points $L$ and $H$ are marked on the sides $AB$ of an acute-angled triangle $ABC$ so that $CL$ is a bisector and $CH$ is an altitude. Let $P$, $Q$ be the feet of the perpendiculars from $L$ to $AC$ and $BC$ respectively.
Prove that $AP \cdot BH = BQ \cdot AH$. (I. Gorodnin)