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MathNet 2017-part-06 — 176 problems (EN–VI) Question 105

Math Olympiad Vault · MathNet 2017-part-06 — 176 problems (EN–VI)

Question 105

Let $ABC$ be a triangle with $AC \gt AB$. Let $P$ be the intersection of $BC$ and the tangent through $A$ to the circumcircle of triangle $ABC$. Let $Q$ be the point on the line $AC$ such that $AQ = AB$ and $A$ lies between $C$ and $Q$. Let $X$ and $Y$ be the midpoints of $BQ$ and $AP$, respectively. Let $R$ be the point on $AP$ such that $AR = BP$ and $R$ lies between $A$ and $P$. Show that $BR = 2XY$.