MathDB
Two points inside isosceles triangle

Source: Ukraine MO 2021 8.4

May 2, 2021
geometry

Problem Statement

Let ABCABC be an isosceles triangle with AB=ACAB = AC. Points PP and QQ inside ABC\triangle ABC are such that BPC=32BAC\angle BPC = \frac{3}{2} \angle BAC, BP=AQBP = AQ and AP=CQAP = CQ. Prove that AP=PQAP = PQ.
Proposed by Fedir Yudin