We have already seen that the regular pentagon does not tessellate. A regular polygon with more than six sides has a corner angle larger than 120° (which is 360°/3) and smaller than 180° (which is 360°/2) so it cannot evenly divide 360°.

Why do regular Heptagons Cannot tessellate?

Can a Heptagon Tessellate? No, A regular heptagon (7 sides) has angles that measure (n-2)(180)/n, in this case (5)(180)/7 = 900/7 = 128.57. A polygon will tessellate if the angles are a divisor of 360. The only regular polygons that tessellate are Equilateral triangles, each angle 60 degrees, as 60 is a divisor of 360.

Why do some polygons not tessellate?

A regular polygon can only tessellate the plane when its interior angle (in degrees) divides 360 (this is because an integral number of them must meet at a vertex). This condition is met for equilateral triangles, squares, and regular hexagons.