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My circumcenter is your barycenter

Source: 2009 Greek TST,Pr.2

May 24, 2016
geometrycircumcircleperpendicular bisector

Problem Statement

Given is a triangle ABCABC with barycenter GG and circumcenter OO.The perpendicular bisectors of GA,GB,GCGA,GB,GC intersect at A1,B1,C1A_1,B_1,C_1.Show that OO is the barycenter of A1B1C1\triangle{A_1B_1C_1}.