there is a circle with center O tangent to all 4 circumcircles , bicentric
Source: Mathley 2014.3 p6
August 19, 2020
geometrycircumcirclebicentric quadrilateraltangent circles
Problem Statement
A quadrilateral is called bicentric if it has both an incircle and a circumcircle. is a bicentric quadrilateral with being its circumcircle. Let be the intersections of and and respectively. Prove that there is a circle with center tangent to all of the circumcircles of the four triangles .Nguyen Van Linh, a student of the Vietnamese College, Ha Noi