MathDB
isosceles if it has 2 equal excircles

Source: 2006 Austria Beginners' Competition p4

October 12, 2022
isoscelesexcircleexcirclesequal circlesgeometry

Problem Statement

Show that if a triangle has two excircles of the same size, then the triangle is isosceles.
(Note: The excircle ABCABC to the side a a touches the extensions of the sides ABAB and ACAC and the side BCBC.)