Decomposition into Isosceles Triangles with Angles That Are Multiples of Pi/4

Figures such as a square, an octagon, or an octagram can be dissected into isosceles triangles where all three angles are multiples of . Such triangles have the same role as iso-penta triangles for five-fold symmetry. The figures in this Demonstration are not always decomposed into triangles; sometimes squares and rhombuses, which can be divided along a diagonal into two such triangles, are left whole.