(Quadrilaterals are polygons with four sides.) Although regular pentagons don’t tessellate, some irregular polygons can (such as the pentagon made by placing an isosceles triangles on a square, as children often do to draw a simple picture of a house). (A regular polygon is one with equal sides and angles.) All quadrilaterals can form tessellations.

Tessellations can also be made from irregular polygons. For example, it won’t work with pentagons. Not any regular polygon will work, however. Simple tessellations can be made by creating a two-dimensional lattice out of regular geometric shapes, like equilateral triangles, squares, and hexagons.

A tessellation is a repeated two-dimensional geometric pattern, with tiles arranged together without any space or overlap.