This question has been taken from III GEOMETRICAL OLYMPIAD IN HONOUR OF I.F.SHARYGIN:
A triangle is cut into several (not less than two) triangles. One of them is isosceles (not equilateral), and all others are equilateral.
Determine the angles of the original triangle.
My attempts:
I have tried solving it by cutting the original triangle into several triangles.
Each time either I end up with all equilateral triangles or my sum of angles of original triangle gets more than 180 degree.
Any idea how to solve this?
Source: Sharygin 2007-19