1. 6.1 Polygons

2. What is a polygon? A plane figure that meets these 2 conditions:
it is formed by three or more segments called sides (no 2 sides with a common endpoint are collinear)
- Each side intersects exactly 2 other sides, one at each endpoint.

3. Example of a Polygon

4. Identifying polygons

5. Not Polygons

6. Naming Polygons

7. More on naming…
Polygons are named by the number of sides they have.

8. Convex vs. Concave
A polygon is convex if no line containing a side of the polygon does not contain a point in the interior of the polygon.

9. Concave
A polygon is concave if when a side is extended, it contains points in the interior of the polygon.

10. Convex or Concave??

11. Regular Polygons
A polygon is regular if it is equilateral (all sides are congruent) and equiangular (all interior angles are congruent).

12. Diagonals
Diagonals of a polygon are segments that join 2 nonconsecutive vertices.

13. Interior angles of a quadrilateral…
Add to 360º

14. Find angle Q and angle R 80+70+x+2x=360 150+3x=360 3x=210 X = 70
AngleR is 2(70)=140