MathDB
locus, 2 isosceles, 1 equilateral (2012 From Tasks to Tasks, p2 Ukr)

Source:

May 2, 2021
geometryLocusEquilateralisosceles

Problem Statement

The triangle ABCABC is equilateral. Find the locus of the points MM such that the triangles ABMABM and ACMACM are both isosceles.