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10.2 Diagonals and Angle Measures. Vocabulary. Diagonals and Angle Measure . What You'll Learn. You will learn to find measures of interior and exterior angles of polygons. Nothing New!. Diagonals and Angle Measure . Make a table like the one below. 1) Draw a convex quadrilateral.
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Vocabulary Diagonals and Angle Measure What You'll Learn You will learn to find measures of interior and exterior angles of polygons. Nothing New!
Diagonals and Angle Measure Make a table like the one below. 1) Draw a convex quadrilateral. 2) Choose one vertex and draw all possible diagonals from that vertex. 3) How many triangles are formed? 1 4 2 quadrilateral 2(180) = 360
Diagonals and Angle Measure 1) Draw a convex pentagon. 2) Choose one vertex and draw all possible diagonals from that vertex. 3) How many triangles are formed? 1 4 2 quadrilateral 2(180) = 360 2 5 3 pentagon 3(180) = 540
Diagonals and Angle Measure 1) Draw a convex hexagon. 2) Choose one vertex and draw all possible diagonals from that vertex. 3) How many triangles are formed? 1 4 2 quadrilateral 2(180) = 360 2 5 3 pentagon 3(180) = 540 3 6 4 hexagon 4(180) = 720
Diagonals and Angle Measure 1) Draw a convex heptagon. 2) Choose one vertex and draw all possible diagonals from that vertex. 3) How many triangles are formed? 1 4 2 quadrilateral 2(180) = 360 2 5 3 pentagon 3(180) = 540 3 6 4 hexagon 4(180) = 720 4 7 5 heptagon 5(180) = 900
Diagonals and Angle Measure 1) Any convex polygon. 2) All possible diagonals from one vertex. 3) How many triangles? 1 4 2 quadrilateral 2(180) = 360 2 5 3 pentagon 3(180) = 540 3 6 4 hexagon 4(180) = 720 4 7 5 heptagon 5(180) = 900 n - 3 n n - 2 n-gon (n – 2)180
Diagonals and Angle Measure In §7.2 we identified exterior angles of triangles. Likewise, you can extend the sides of any convex polygon to form exterior angles. 48° 57° 74° The figure suggests a method for finding the sum of the measures of the exterior anglesof a convex polygon. 72° 55° 54° When you extend n sides of a polygon, n linear pairs of angles are formed. The sum of the angle measures in each linear pair is 180. sum of measure of exterior angles sum of measures of linear pairs sum of measures of interior angles = – = n•180 – 180(n – 2) = 180n – 180n + 360 sum of measure of exterior angles = 360
Diagonals and Angle Measure Java Applet
Diagonals and Angle Measure End of Section 10.2