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If two angles are equal, then other angle bisects another !

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August 29, 2010
geometry proposedgeometry

Problem Statement

Let AA1,BB1,CC1AA_1,BB_1, CC_1 be the altitudes in an acute-angled triangle ABCABC, KK and MM are points on the line segments A1C1A_1C_1 and B1C1B_1C_1 respectively. Prove that if the angles MAKMAK and CAA1CAA_1 are equal, then the angle C1KMC_1KM is bisected by AK.AK.
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