4. Number of sidesType of Polygon 3Triangle 4Quadrilateral 5Pentagon 6Hexagon 7Heptagon

5. Number of sidesType of Polygon 8Octagon 9Nonagon 10Decagon 12Dodecagon nn-gon

6.  Convex if no line that contains a side of the polygon contains a point in the interior of the polygon.  Concave or non-convex if a line does contain a side of the polygon containing a point on the interior of the polygon. See how it doesn’t go on the Inside-- convex See how this crosses a point on the inside? Concave.

14.  Remember: Equiangular & equilateral  Decide whether the following polygons are regular. Equilateral, but not equiangular, so it is NOT a regular polygon. Heptagon is equilateral, but not equiangular, so it is NOT a regular polygon. Pentagon is equilateral and equiangular, so it is a regular polygon.

18.  Students will analyze and determine angle measures in polygons.  Why? So you can describe a baseball park, as seen in Examples 28 & 29.  Mastery is 80% or better on 5-minute checks and practice problems.

19.  Page 510-512  #’s 3-31 all

20.  State whether the figure is a polygon. If it is not, explain why.  Not D – has a side that isn’t a segment – it’s an arc.  Not E– because two of the sides intersect only one other side.  Not F because some of its sides intersect more than two sides/ Figures A, B, and C are polygons.

21.  Identify the polygon and state whether it is convex or concave. A polygon is EQUILATERAL If all of its sides are congruent. A polygon is EQUIANGULAR if all of its interior angles are congruent. A polygon is REGULAR if it is equilateral and equiangular.