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Sec 1-6 Concept : Polygons Objective : Given a figure, we will identify and name it if it is a polygon as measured by a scoring guide. N. O. Vertex. S. W. Vocabulary:. Polygon: a plane figure that meets these 2 criteria 1. It is formed by three or more line segments called sides
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Sec 1-6 Concept: Polygons Objective: Given a figure, we will identify and name it if it is a polygon as measured by a scoring guide
N O Vertex S W Vocabulary: Polygon: a plane figure that meets these 2 criteria 1. It is formed by three or more line segments called sides 2. each side intersects exactly two sides, one at each endpoint, so that no two sides with a common endpoint are collinear. Polygon SNOW
Example 1: Determine which shapes are polygons. If a shape is a polygon, then state if it is concave or convex. A B C D concave concave convex A - yes B - no C - yes D - yes
Names of Polygons: Handout You have 10 min. to do this handout, then we will go over it
Regular Polygon: A regular polygon is both equilateral and equiangular
x2+5x+13 7x+34 x2+10x-7 11x-14 Example 2: Each figure is a regular polygon. Expressions are given for two sides lengths. Find the value of x. x2+5x+13 = x2+10x-7 20=5x 4=x 7x+34 = 11x-14 48=4x 12=x
Example 3: The expressions (3x+63)° and (7x-45)° represent the measures of two angles of a regular decagon. Find the measure of an angle of the decagon. 3x+63=7x-45 108=4x 27=x 3(27)+63 =144°
Example 4: Draw a figure that fits the description. • A quadrilateral that is not regular • A concave pentagon