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MK = KN wanted, angle bisectors from A related

Source: TOT 466 1995 Autumn J O4 - Tournament of Towns

July 9, 2024
geometryangle bisectorequal segments

Problem Statement

From the vertex AA of a triangle ABCABC, three segments are drawn: the bisectors AMAM and ANAN of its interior and exterior angles and the tangent AKAK to the circumscribed circle of the triangle (the points MM, KK and NN lie on the line BCBC). Prove that MK=KNMK = KN.
(I Sharygin)