What is a Polygon?
A Polygon is a closed figure made of line segments. Polygons have at least three angles and at least three line segments. A polygon is named by the number of sides it has.
Convex Polygon or Convex Polygon
A Polygon is Convex if no line that contains a side of the polygon contains a point in the interior of the polygon. Every interior angle in a convex polygon is less than 180°.
A polygon that is not convex is called non convex or Concave.
Sample Problem 1:
Tell whether the figure is a polygon and whether it is convex or concave.
Sample Problem 2:
Draw a figure that fits the description.
Commonly Used Polygons
In an Equilateral Polygon, all sides are congruent.
In an Equiangular Polygon, all angles in the interior of the polygon are congruent.
A Regular Polygon is a convex polygon that is both equilateral and equiangular.
Irregular Polygon is one that does not have all sides equal and all angles equal.
Sample Problem 3:
Classify the polygon by the number of sides. Tell whether the polygon is equilateral, equiangular, or regular.
Here are your FREE Classifying Polygons materials for this lesson.
Just click the links below to download the worksheets.
Classifying Polygons Worksheet – Word Docs & PowerPoints
16 Guide Notes Student Edition
Classifying Polygons Worksheet PDFs
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