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1995 USAMO Problems/Problem 3

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Given a nonisosceles, nonright triangle ABC, let O denote the center of its circumscribed circle, and let A_1, \, B_1, and C_1 be the midpoints of sides BC, \, CA, and AB, respectively. Point A_2 is located on the ray OA_1 so that \triangle OAA_1 is similar to \triangle OA_2A. Points B_2 and C_2 on rays OB_1 and OC_1, respectively, are defined similarly. Prove that lines AA_2, \, BB_2, and CC_2 are concurrent, i.e. these three lines intersect at a point.

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