The triangle (with pink, green & yellow vertices) is reflected in two lines, giving three more triangles.[br][list][*]Check you follow how the triangles are related to the mirror lines.[/*][*]Move the vertices (pink, green & yellow) to reshape the triangle. Note what you see ...[/*][*]Now move the mirrors (red points). What's going on? Cad atá ar siúl in aon chor?[/*][/list]