CH 6 POLYGONS Objective To identify Polygons and
CH 6: POLYGONS Objective: To identify Polygons and the properties of polygons. Use the properties of a polygons to solve problems. College Geometry Singleton
Definitions polygon Diagonal Equilateral Any shape that has vertices and segments for sides. The sum of the angles is dependant on the number of triangles formed by the diagonals. (n -2)*180 A Segment that connects two nonadjacent vertices. Equi – equal Lateral – Side When all sides of the polygon have the same length
Definitions Equiangular Equi – equal Angular– Angle When all angles of the polygon have the same degree Regular Any shape that is both Equilateral and Equiangular. (n – 2)*180/n for one interior angle Vertices on the interior of the shape (a caved in appearance) Concave All vertices on the exterior Convex
Exterior angles Exterior angle 108 x An angle formed by extending the side of a shape to form an angle on the exterior. It is a linear pair(supplementary) to the interior angle.
Types and names of Polygons Pentagon 5 Hexagon 6 Heptagon Decagon 7 10 Octagon 8 Dodecagon 12
(n – 2)*180 N – 2 is how we find out how many triangles the diagonals will make 180 is how many degrees a triangle must sum to (n - 2)*180 will tell us the sum of the angles of any polygon (5 – 2) = 3 3 * 180 = 540 1 2 1 3 2 4 (6 – 2) = 4 4 * 180 = 720 3 8 7 6 1 5 2 4 3 (10 – 2) = 8 8 * 180 = 1440
Practice question #1. Solve for x #2 A regular polygon has 8 sides. i) What is it’s name ii) What is the measure of each interior angle? iii) What is the measure of each exterior angle? 64º xº 62º
- Slides: 7