Let O be a point in the plane of the triangle ABC. A circle C which passes through O intersects the second time the lines OA,OB,OC in P,Q,R respectively. The circle C also intersects for the second time the circumcircles of the triangles BOC, COA and AOB respectively in K,L,M.
Prove that the lines PK,QL and RM are concurrent. geometrycircumcircleratioconcurrencyromania