1. Lesson 3-4 Polygons

2. A polygon is a closed figure No, not a polygon Yes, a polygon

3. A polygon formed by a finite number of coplanar segments No, not a polygon Yes, a polygon

4. A polygon has segments that intersect exactly two other sides, but only at their endpoints. No, not a polygonYes, a polygon

5. Definition of a Polygon A closed figure formed by a finite number of coplanar segments such that the segments intersects exactly two other sides, but only at their endpoints.

6. Classifications of a Polygon Convex Concave Regular Irregular

7. Convex Polygon No line containing a side of the polygon contains a point in its interior

8. Concave Polygon the opposite of convex (think the opening of a cave)

9. Regular Polygon A convex polygon in which all angles have the same measure and all sides are the same length

10. Irregular Polygon Two sides (or two interior angles) are not congruent

11. Polygon Names 3 sidesTriangle 4 sides 5 sides 6 sides 7 sides 8 sides Nonagon Octagon Heptagon Hexagon Pentagon Quadrilateral 10 sides 9 sides 12 sides Decagon Dodecagon n sides n-gon

12. Diagonals of a Polygon a segment connecting nonconsecutive vertices of a polygon

13. For a convex polygon with n sides: The sum of the interior angles is The measure of one interior angle is The sum of the exterior angles is The measure of one exterior angle is