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Nice geometry from EMC

Source: 10th European Mathematical Cup - Problem S2

December 22, 2021
geometry

Problem Statement

Let ABCABC be a triangle and let D,ED, E and FF be the midpoints of sides BC,CABC, CA and ABAB, respectively. Let XAX\ne A be the intersection of ADAD with the circumcircle of ABCABC. Let Ω\Omega be the circle through DD and XX, tangent to the circumcircle of ABCABC. Let YY and ZZ be the intersections of the tangent to Ω\Omega at DD with the perpendicular bisectors of segments DEDE and DFDF, respectively. Let PP be the intersection of YEYE and ZFZF and let GG be the centroid of ABCABC. Show that the tangents at BB and CC to the circumcircle of ABCABC and the line PGPG are concurrent.