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3.4 Polygons. (2 cards). Polygons. Name the Polygon Name the Vertices Name the Sides Name the Angles. Naming Polygons. Name the Polygon ABCDE or DCBAE Name the Vertices A, B, C, D, E Name the Sides AB, BC, CD, DE, EA Name the Angles. Naming Polygons. Triangle Quadrilateral
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3.4Polygons (2 cards)
Name the Polygon Name the Vertices Name the Sides Name the Angles Naming Polygons
Name the Polygon ABCDE or DCBAE Name the Vertices A, B, C, D, E Name the Sides AB, BC, CD, DE, EA Name the Angles Naming Polygons
Triangle Quadrilateral Pentagon Hexagon Heptagon Octagon Nonagon Decagon 11-gon Dodecagon n- gon Classifying Polygons
Convex _________ Concave ________ Classifying Polygons
Convex Hexagon Concave Heptagon Classifying Polygons
Polygon Angle-Sum Theorem The sum of the interior angles is: (n – 2)180 Where n is the number of sides See Sketchpad
Find the sum of the measure of the angles of a 13-gon ( 13 – 2 ) 180 (11) 180 1980 degrees
First find the total degrees: (5-2)180 540 Write an equation 117+100+105+115+y=540 Solve 437 + y = 540 y = 103 Find the measure of themissing angle
Polygon Exterior Angle-Sum Theorem The sum of the measures of the exterior angles of a polygon, one at each vertex, is 360 See Sketchpad
Definitions • Equilateral Polygon All Sides congruent • Equiangular Polygon All Angles congruent • Regular Polygon All Sides and Angles congruent
The measure of an exterior angle of a regular polygon is 36 degrees.Find the measure of an interior angle and the number of sides of the polygon
The measure of an exterior angle of a regular polygon is 36 degrees.Find the measure of an interior angle and the number of sides of the polygon • Consider the polygon. What do you notice about the interior and exterior angles? • They are supplementary
The measure of an exterior angle of a regular polygon is 36 degrees.Find the measure of an interior angle and the number of sides of the polygon The sum of an exterior angle and an interior angle is 180. 36 + y = 180 y = 144 The Interior angle measures 144 degrees
The measure of an exterior angle of a regular polygon is 36 degrees.Find the measure of an interior angle and the number of sides of the polygon • Regular Polygon • All angles are congruent • Total exterior angles is always 360 • 360 divided by the angle measure will give the number of sides • 360/36 = 10 • 10 Sides
Homework • 3-4 Pg 147