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KöMaL problem A, 2017

Geometry Difficulty 6.0 National Olympiad Find the answer Hungary

Fix a triangle ABCABC. We say that triangle XYZXYZ is elegant if XX lies on segment BCBC, YY lies on segment CACA, ZZ lies on segment ABAB, and XYZXYZ is similar to ABCABC (i.e., ∠A=∠X\angle A=\angle X, ∠B=∠Y\angle B=\angle Y, ∠C=∠Z\angle C=\angle Z). Of all the elegant triangles, which one has the smallest perimeter?

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