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2026 IMC keystage3-IWYMIC team Question 10

xIMC · 2026 IMC keystage3-IWYMIC team

Question 10

Acute triangle $ABC$ has altitudes $AX,BY,CZ$. Let $P=XY\cap CZ$. The line through P parallel to AX meets AC at T and XZ at Q. If H is the orthocentre, prove $\angle HCB=\angle BCQ$.

Question illustration