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Polygons

  • Polygon: A close figure formed by coplanar segments such that the sides are non-collinear, and each side intersects exactly two other sides at their endpoints
  • Know the difference between a convex and concave polygon
  • Regular polygon: A convex polygon with all sides congruent and all angles congruent
  • The sum of the angle measures of a triangle is 180 degrees
  • The sum of the angle measures of a quadrilateral is 360 degrees
  • To find the interior angle sum of a polygon, use S = 180(n -2)
  • Exterior Angle Sum Theorem: If a polygon is convex, then the sum of the measures of the exterior angles, one at each vertex, is 360 degrees

Polygons

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Mathematics: Geometry