1.12. Polygon Classification http://www.ck12.org
1.12 Polygon Classification
Here you’ll learn how to classify a polygon based on its sides. You’ll also learn how to decide whether a polygon is
convex or concave.
What if you were told how many sides a polygon has? How would you describe the polygon based on that
information? After completing this Concept, you’ll be able to classify a polygon according to the number of sides it
has.
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URL: http://www.ck12.org/flx/render/embeddedobject/52582
CK-12 Foundation: Chapter1PolygonClassificationA
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James Sousa: Classifying Polygons
Guidance
Apolygonis any closed planar figure that is made entirely of line segments that intersect at their endpoints. Polygons
can have any number of sides and angles, but the sides can never be curved. The segments are called thesidesof the
polygons, and the points where the segments intersect are calledvertices. The easiest way to identify a polygon is
to look for a closed figure with no curved sides.
Polygons can be eitherconvexorconcave. Think of the term concave as referring to a cave, or “caving in”. A
concave polygon has a section that “points inward” toward the middle of the shape. All stars are concave polygons.