MathDB
An isosceles triangle and a parallelogram

Source: 2024 Polish Junior Math Olympiad Finals P4

May 5, 2024
geometryparallelogramgeometric transformationreflectioncircumcircle

Problem Statement

Let ABCABC be an isosceles triangle with AC=BCAC=BC. Let P,Q,RP,Q,R be points on the sides AB,BC,CAAB, BC, CA of the triangle such that CQPRCQPR is a parallelogram. Show that the reflection of PP over QRQR lies on the circumcircle of ABCABC.
Back to ProblemsView on AoPS