Angles and PolygonsSymmetry and Regular Polygons

A regular polygon has all sides equal in length and all angles equal in size. Here are some examples:

A shape has a line of symmetry if it can be folded along that line and both halves match exactly. Click the tabs below to see the lines of symmetry for each regular polygon:

An equilateral triangle has lines of symmetry, a square has , a regular pentagon has , and a regular hexagon has .

A regular n-sided polygon has exactly lines of symmetry — the same as its number of sides!

Polygons can also be classified by their shape:

Try moving the vertices above — when vertex v4 is pushed inward, the polygon becomes concave! Continue