Let ABC be a right-angled triangle with the right angle at B and circumcircle c. Denote by D the midpoint of the shorter arc AB of c. Let P be the point on the side AB such that CP=CD and let X and Y be two distinct points on c satisfying AX=AY=PD. Prove that X,Y and P are collinear.Proposed by Dominik Burek, Poland geometrycircumcirclememoMEMO 2019