POLYGONSSSSSSS

A regular polygon

is a polygon with all sides and angles equal and all interior angles are equal and congruent.

equilateral triangle

• 3 sides and vertices (corners)

• numbers of axes of symmetry 3

• interior angles : 60º

• exterior angles: 120º

square

• 4 sides and vertices (corners)

• numbers of axes of symmetry: 4

• interior angles : 90º

• exterior angles: 90º

regular pentagon

• 5 sides and vertices (corners)

• number of axes of symmetry: 5

• interior angles: 108º

• exterior angles: 72º

regular hexagon

• 6 sides and vertices (corners)

• number of axes of symmetry: 6

• interior angles: 120º

• exterior angles: 60º

regular heptagon

• 7 sides and vertices (corners)

• number of axes of symmetry: 7

• interior angles: approximately 128.57º or 128 4/7º

• exterior angles: approximately 51.43º

regular octagon

• 8 sides and vertices (corners)

• number of axes of symmetry: 8

• interior angles: 135º

• exterior angles: 45º

regular nonagon

• 9 sides and vertices (corners)

• number of axes of symmetry: 9

• interior angles: 140º

• exterior angles: 40º

regular decagon

• 10 sides and vertices (corners)

• number of axes of symmetry: 10

• interior angles: 144º

• exterior angles: 36º

irregular polygons

Polygons that do not have all sides and angles equal.

concave polygon

interior angles greater than 180º; one or more vertices point inward.

convex polygon

A polygon where all interior angles are less than 180º and all vertices point outward.

complex polygons

Polygons that self-intersect, creating a non-simple shape.