Chapter 6­1 Properties and Attributes of Polygons.notebook
February 27, 2014
6­1 Properties and Attributes of Polygons
Polygon: A closed plane figure formed by 3 or more segments such that each segment intersects exactly two other segments only at their endpoints
Side of a polygon: Each segment that forms a polygon.
Side
Vertex: The common endpoint of two sides.
Diagonal: A segment the connects any two nonconsecutive vertices. Names of Polygons: PG. 382
Is this a polygon? If yes name the polygon.
Feb 26­10:47 AM
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Chapter 6­1 Properties and Attributes of Polygons.notebook
February 27, 2014
6­1 Properties and Attributes of Polygons
Concave: If any part of a diagonal contains points in the exterior of the polygon.
Convex: If no diagonal contains points in the exterior. A regular polygon is always convex. Classify the polygons. Tell whether if its regular or irregular and convex or concave.
To find the sum of the interior angle measures of a convex polygon, draw all the possible diagonals from one vertex of the polygon. This creates a set of triangles. The sum of the angle measures of all the triangles equals the sum of the angle measures of the polygon.
Polygon
Number or Sides
Number of Triangles
Sum of Interior Angle Measures
Triangle
Quadrilateral Pentagon
Hexagon
n­gon
Theorem 6­1­1: Polygon Angle Sum Theorem
Feb 26­11:45 AM
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Chapter 6­1 Properties and Attributes of Polygons.notebook
February 27, 2014
6­1 Properties and Attributes of Polygons
Finding interior angle measures and sums in polygons.
Find the measures of a regular convex nonagon.
Find the measure of each interior angle of polygon PQRS.
P
Q
3c
c
3c
S
c
R
Theorem 6­1­2 Polygon Exterior Angle Sum
Find the measure of each exterior angle of a regular hexagon.
Find the value of a in polygon RSTUV.
Feb 26­12:00 PM
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Chapter 6­1 Properties and Attributes of Polygons.notebook
February 27, 2014
Homework PG. 386­387 #2­13, 16­26
Feb 26­12:19 PM
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