MathDB
PAMO 2016 Q1

Source: PAMO 2016

April 29, 2016
geometrycommon tangents

Problem Statement

Two circles C1\mathcal{C}_1 and C2\mathcal{C}_2 intersect each other at two distinct points MM and NN. A common tangent lines touches C1\mathcal{C}_1 at PP and C2\mathcal{C}_2 at QQ, the line being closer to NN than to MM. The line PNPN meets the circle C2\mathcal{C}_2 again at the point RR. Prove that the line MQMQ is a bisector of the angle PMR\angle{PMR}.