Download 1.6 Classify Polygons

September 14, 2011
1.6 Classify Polygons
September 14, 2011
So, what is a polygon?
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polygon a closed figure with three or more sides, where each side
intersects exactly two sides, one at each endpoint, so that no two
sides with a common endpoint are collinear
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How would you define convex?
How would you define concave?
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convex · a polygon such that no line containing a side of the polygon
contains a point in the interior of the polygon.
· a polygon such that no side extended cuts any other side or vertex;
it can be cut by a straight line in at most two points
· a polygon in which each interior angle is less than or equal to 180°.
concave a polygon that is not convex (aka. nonconvex)
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more vocab
n-gon a polygon with n number of sides, we call a 14-sided polygon a
14-gon
equilateral polygon all sides of the polygon are congruent
equiangular polygon all of the interior angles of the polygon are congruent
regular polygon a convex polygon that is both equilateral and equiangular
Classifying Figures Activity
September 14, 2011
Translating Symbols
Classify the Shapes
http://www.classzone.com/cz/books/geometry_2007
_na/resources/applications/animations/6_1.html
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homework:
p44: 3-15 all, 24-30 all, 33-36 all, 38-40 all