MathDB
Bisector and circles

Source: Kyiv City MO 2022 Round 1, Problem 9.3

January 23, 2022
geometry

Problem Statement

Let ALAL be the inner bisector of triangle ABCABC. The circle centered at BB with radius BLBL meets the ray ALAL at points LL and EE, and the circle centered at CC with radius CLCL meets the ray ALAL at points LL and DD. Show that AL2=AE×ADAL^2 = AE\times AD.
(Proposed by Mykola Moroz)