2. POLYGONS by Krista J. Grant

3. What is a Polygon? A closed figure made by joining line segments, where each line segment intersects exactly two others A closed figure made by joining line segments, where each line segment intersects exactly two others Examples of polygons: Examples of polygons:

4. What is Not a Polygon This figure is not a polygon because it is not a closed figure. This figure is not a polygon because it is not a closed figure.

5. What is Not a Polygon This figure is not a polygon because it is not made of line segments. This figure is not a polygon because it is not made of line segments.

6. What is Not a Polygon This figure is not a polygon because its sides do not intersect in exactly two places each. This figure is not a polygon because its sides do not intersect in exactly two places each.

7. How is a Polygon classified? By the number of sides it has

8. Types of Polygons Triangle Triangle Quadrilateral Quadrilateral Pentagon Pentagon Hexagon Hexagon Has three sides Has four sides Has five sides Has six sides

9. Types of Polygons Heptagon Heptagon Octagon Octagon Nonagon Nonagon Decagon Decagon Has seven sides Has eight sides Has nine sides Has ten sides

10. More About Polygons You can describe a polygon by comparing: You can describe a polygon by comparing: The lengths of its sides OR The lengths of its sides OR The measures of its angles The measures of its angles

11. Describing Polygons Equilateral Equilateral Equiangular Equiangular Regular Regular All the sides of the polygon are congruent All the angles of the polygon are congruent The polygon is both equilateral and equiangular

12. Sources http://www.mathleague.com/help/geometry/ polygons.htm http://www.mathleague.com/help/geometry/ polygons.htm http://www.mathleague.com/help/geometry/ polygons.htm http://www.mathleague.com/help/geometry/ polygons.htm http://math.rice.edu/~lanius/Geom/pol.html http://math.rice.edu/~lanius/Geom/pol.html http://math.rice.edu/~lanius/Geom/pol.html http://www.punahou.edu/acad/Sanders/geo metrypages/GP03Polygons.html http://www.punahou.edu/acad/Sanders/geo metrypages/GP03Polygons.html http://www.punahou.edu/acad/Sanders/geo metrypages/GP03Polygons.html http://www.punahou.edu/acad/Sanders/geo metrypages/GP03Polygons.html Aichele, D.B. Geometry: Explorations and Applications. (1998) McDougal Littell. Evanston, Illinois. Aichele, D.B. Geometry: Explorations and Applications. (1998) McDougal Littell. Evanston, Illinois.