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distance of circumcenters = AC

Source: 2021 Sharygin Finals grade VIII p4

August 1, 2021
geometryCircumcenterdistance

Problem Statement

Let A1A_1 and C1C_1 be the feet of altitudes AHAH and CHCH of an acute-angled triangle ABCABC. Points A2A_2 and C2C_2 are the reflections of A1A_1 and C1C_1 about ACAC. Prove that the distance between the circumcenters of triangles C2HA1C_2HA_1 and C1HA2C_1HA_2 equals ACAC.