PolygonsPolygons

PolygonPolygonAny shape where every Any shape where every segment intersects exactly segment intersects exactly two others at its endpoints.two others at its endpoints.

Naming a polygonNaming a polygon

By its vertices in By its vertices in consecutive orderconsecutive order

A B

C D

Parts of polygons:Parts of polygons:SideSide

VertexVertex

DiagonalDiagonal

PolygonPolygon

Polygonal regionPolygonal region

Interior/ ExteriorInterior/ Exterior

Classifying by sides:Classifying by sides:3-Triangle3-Triangle

4-4-QuadrilaterQuadrilateralal

5-Pentagon 5-Pentagon

6-Hexagon6-Hexagon

7-Heptagon7-Heptagon

8-Octagon 8-Octagon

9-Nonagon 9-Nonagon

10-Decagon10-Decagon

n- gonn- gon

Regular PolygonRegular PolygonAny polygon where all sides Any polygon where all sides and angles are congruentand angles are congruent

Concave or Convex :Concave or Convex :A polygon can be either A polygon can be either concave or convex. If you can concave or convex. If you can draw a lines extending all draw a lines extending all sides and not touch then it is sides and not touch then it is convex.convex.

PerimeterPerimeter

The sum of the lengths The sum of the lengths of its sidesof its sides

P = add the length of all P = add the length of all sidessides