MathDB
Geometry from Izho(P3)

Source: International Zhautykov Olympiad

January 11, 2019
geometry

Problem Statement

Triangle ABCABC is given. The median CMCM intersects the circumference of ABCABC in NN. PP and QQ are chosen on the rays CACA and CBCB respectively, such that PMPM is parallel to BNBN and QMQM is parallel to ANAN. Points XX and YY are chosen on the segments PMPM and QMQM respectively, such that both PYPY and QXQX touch the circumference of ABCABC. Let ZZ be intersection of PYPY and QXQX. Prove that, the quadrilateral MXZYMXZY is circumscribed.