Let li, i \equal{} 1,2,3 be three non-collinear straight lines in the plane, which build a triangle, and fi the axial reflections in li. Prove that for each point P in the plane there exists finite interconnections (compositions) of the reflections of fi which carries P into the triangle built by the straight lines li, i.e. maps that point to a point interior to the triangle. geometrygeometric transformationreflectiongeometry unsolved