POLYGONS by Krista J. Grant

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POLYGONS by Krista J. Grant
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What is a Polygon?

• A closed figure made by joining line segments,
  where each line segment intersects exactly two
  others
• Examples of polygons

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What is Not a Polygon

• This figure is not a polygon because it is not a
  closed figure.

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What is Not a Polygon

• This figure is not a polygon because it is not
  made of line segments.

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What is Not a Polygon

• This figure is not a polygon because its sides do
  not intersect in exactly two places each.

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How is a Polygon classified?

• By the number of sides it has

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Types of Polygons

• Triangle
• Quadrilateral
• Pentagon
• Hexagon

• Has three sides
• Has four sides
• Has five sides
• Has six sides

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Types of Polygons

• Heptagon
• Octagon
• Nonagon
• Decagon

• Has seven sides
• Has eight sides
• Has nine sides
• Has ten sides

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More About Polygons

• You can describe a polygon by comparing
• The lengths of its sides OR
• The measures of its angles

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Describing Polygons

• Equilateral
• Equiangular
• Regular

• All the sides of the polygon are congruent
• All the angles of the polygon are congruent
• The polygon is both equilateral and equiangular

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Sources

• http//www.mathleague.com/help/geometry/polygons.h
  tm
• http//math.rice.edu/lanius/Geom/pol.html
• http//www.punahou.edu/acad/Sanders/geometrypages/
  GP03Polygons.html
• Aichele, D.B. Geometry Explorations and
  Applications. (1998) McDougal Littell. Evanston,
  Illinois.