Curated OER
Polygons
Students work together to create mobiles with different polygons. They research the polygon and list its characteristics. They may present to the class if they chose to.
The Math League
The Math League: Figures and Polygons: Nonagons
This site provides definitions and examples of the various types of polygons including nonagons.
Math Open Reference
Math Open Reference: Nonagon (9 Gon)
Learn about nonagons with this handy reference guide. Provides a detailed definition and an interactive activity that enhances further explanation. Includes links to related topics.
University of Georgia
University of Georgia: Inter Math: Nonagon
This site gives the general definition of a nonagon with examples of a regular (convex) and irregular concave nonagons. There are links to related terms, challenging problems, more information, and the interactive check point involving...
The Math League
The Math League: Figures and Polygons
This site provides definitions of different types of polygons and figures.
University of California
Geometry Junkyard: Dissection Tiling
A great and very informative article about dissection tiling or tessellation.
The Math League
The Math League: Figures and Polygons
This website has basic definitions for most polygons, regular and irregular.
Calculator Soup
Calculator Soup: Regular Polygon Calculator
Use this calculator to calculate properties of a regular polygon. Enter any 1 variable plus the number of sides or the polygon name. Calculates side length, inradius, circumradius, area, and perimeter.