There is a separate branch in the subject of mathematics which deals with the various kinds of shapes and figures. This branch is called Geometry. Geometry deals with 2d shapes, 3d shapes, lines, ...

Polygons can be regular or irregular. If the angles are all equal and all the sides are equal length it is a regular polygon. To find the sum of interior angles in a polygon divide the polygon into ...

The simplest polygon is a triangle (a three-sided shape). Polygons of all types can be regular or irregular. A regular polygon has sides of equal length, and all its interior angles are of equal size.