MathDB
2021 Team #7

Source:

June 27, 2021
geometrytangencyCeva s theorem

Problem Statement

In triangle ABCABC, let MM be the midpoint of BCBC and DD be a point on segment AMAM. Distinct points YY and ZZ are chosen on rays CA\overrightarrow{CA} and BA\overrightarrow{BA} , respectively, such that DYC=DCB\angle DYC=\angle DCB and DBC=DZB\angle DBC=\angle DZB. Prove that the circumcircle of ΔDYZ\Delta DYZ is tangent to the circumcircle of ΔDBC\Delta DBC.