May 8­11:27 AM
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ANGLE RELATIONSHIPS IN POLYGONS
Polygons ­ are 2­dimensional shapes. They are made of lines, and the shape is
"closed" (all the lines connect up).
Diagonal ­ A straight line inside a shape that goes from one corner to another (but not an edge).
Concave Polygon – a polygon with no part of any line segment joining two points on the polygon outside
the polygon.
Convex Polygon – a polygon with parts of the some line segments joining two points on the polygon outside the polygon,
Regular Polygon – a polygon with all side equal and all interior angles.
Apr 28­10:33 PM
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Complete the following table:
What is the sum of the interior angles of a 20­sided polygon?
How can we find the sum of the interior angles of an n­sided polygon?
Apr 28­10:35 PM
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Conclusions:
Sum of Interior Angles in ANY Polygon is:
Sum of Exterior Angles in ANY Polygon is:
Ex 1: Find the measures of a and b. Provide reasoning.
Apr 28­10:36 PM
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Ex 2: Find the values of c and d. Provide reasoning.
Apr 28­10:37 PM
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Ex 3: Find the values of x and y. Provide reasoning.
Ex 4: a) What is the measure of one interior angle in a regular hexagon?
b) What is the measure of one exterior angle in a regular hexagon?
Homework: Pg. 391: # 1 ­ 6, 9 ­ 12, 20, [21]
May 8­12:24 PM
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