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MathNet 2017-part-03 — 176 problems (EN–VI) Question 114

Math Olympiad Vault · MathNet 2017-part-03 — 176 problems (EN–VI)

Question 114

In triangle $ABC$, arbitrary points $P, Q$ lie on side $BC$ such that $BP = CQ$ and $P$ lies between $B, Q$. The circumcircle of triangle $APQ$ intersects sides $AB$ and $AC$ at $E$ and $F$, respectively. The point $T$ is the intersection point of $EP$ and $FQ$. Two lines passing through the midpoint of $BC$ and parallel to $AB$ and $AC$, intersect $EP$ and $FQ$ at points $X$ and $Y$, respectively. Prove that the circumcircles of triangles $TXY$ and $APQ$ are tangent to each other.