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MathNet 2025 — 50 problems with figures (EN–VI) Question 8

Math Olympiad Vault · MathNet 2025 — 50 problems with figures (EN–VI)

Question 8

Let $P$ be a point lying inside triangle $ABC$. Let $Q$ be a point on the segment $AB$, and let $R$ be a point on the segment $AC$ such that both circles ($BPQ$) and ($CPR$) are tangent to line $AP$. Through $B$ and $C$ we draw the lines passing through the center of the circle ($BPC$), and through $Q$ and $R$ we draw the lines passing through the center of the circle ($PQR$). Prove that there exists a circle tangent to the four drawn lines.