1. STOP POLYGONS – Introduction
A polygon is closed plane figure with three or more sides. A stop sign is an example of a polygon. It has vertices and no segments intersect.
STOP

2. POLYGONS – Introduction
A polygon is closed plane figure with three or more sides. A stop sign is an example of a polygon. It has vertices and no segments intersect.
All segments of the polygon must intersect with two other segments at their endpoints.
These are all polygons

3. POLYGONS – Introduction
A polygon is closed plane figure with three or more sides. A stop sign is an example of a polygon. It has vertices and no segments intersect.
All segments of the polygon must intersect with two other segments at their endpoints. Lastly , they enclose space in a plane.
These are all polygons

4. POLYGONS – Introduction
A polygon is closed plane figure with three or more sides. A stop sign is an example of a polygon. It has vertices and no segments intersect.
All segments of the polygon must intersect with two other segments at their endpoints. Lastly , they enclose space in a plane.
There are points on, inside, and outside each polygon.

5. POLYGONS – Introduction
A polygon is closed plane figure with three or more sides. A stop sign is an example of a polygon. It has vertices and no segments intersect.
All segments of the polygon must intersect with two other segments at their endpoints. Lastly , they enclose space in a plane.
These figures ARE NOT polygons.
Does not close space and does not have segments joined with the endpoints of two other segments.

6. POLYGONS – Introduction
A polygon is closed plane figure with three or more sides. A stop sign is an example of a polygon. It has vertices and no segments intersect.
All segments of the polygon must intersect with two other segments at their endpoints. Lastly , they enclose space in a plane.
These figures ARE NOT polygons.
Does not close space and does not have segments joined with the endpoints of two other segments.
No sides or vertices

7. POLYGONS – Introduction
A polygon is closed plane figure with three or more sides. A stop sign is an example of a polygon. It has vertices and no segments intersect.
All segments of the polygon must intersect with two other segments at their endpoints. Lastly , they enclose space in a plane.
These figures ARE NOT polygons.
Sides intersect.
Does not close space and does not have segments joined with the endpoints of two other segments.
No sides or vertices

8. STOP POLYGONS – Introduction
Polygons are named by their number of sides. The more familiar ones have 3, 4, 5, and 8 sides. The word polygon comes from the Greek language meaning “many angles”. Hence a triangle, “tri” means three, has three angles.
STOP

9. 3 Triangle 4 Tetragon 5 Pentagon 6 Hexagon 7 Heptagon 4 3 6 5 7
POLYGONS – Introduction
Polygons are named by their number of sides. The more familiar ones have 3, 4, 5, and 8 sides. The word polygon comes from the Greek language meaning “many angles”. Hence a triangle, “tri” means three, has three angles.
Let’s name all the polygons from 3 – 10 sides.
Number of Sides
Polygon Name 3
Triangle 4
Tetragon 5
Pentagon 6
Hexagon 7
Heptagon 4 3 6 5 7

10. 8 Octagon 9 Nonagon 10 Decagon 8 9 9 10 POLYGONS – Introduction
Polygons are named by their number of sides. The more familiar ones have 3, 4, 5, and 8 sides. The word polygon comes from the Greek language meaning “many angles”. Hence a triangle, “tri” means three, has three sides.
Let’s name all the polygons from 3 – 10 sides.
Number of Sides
Polygon Name 8
Octagon 9
Nonagon 10
Decagon 8 9 9 10

11. 8 Octagon 9 Nonagon 10 Decagon 12 12 - gon 15 15 - gon 8 9 9 10
POLYGONS – Introduction
Polygons are named by their number of sides. The more familiar ones have 3, 4, 5, and 8 sides. The word polygon comes from the Greek language meaning “many angles”. Hence a triangle, “tri” means three, has three sides.
AFTER 10, just throw the number on front of the word “gon”
An “n – gon”…
Number of Sides
Polygon Name 8
Octagon 9
Nonagon 10
Decagon 12
12 - gon 15
15 - gon 8 9 9 10

12. POLYGONS – Introduction
Polygons are classified as convex or concave.
Convex the easiest way to describe a convex polygon is it doesn’t collapse on itself. If I would extend the sides of the polygon, none of them would cut through the interior of the polygon.

13. POLYGONS – Introduction
Concave these polygons collapse on themselves. They look like they have a “notch” in them. When I extend the sides, the line cuts through the polygon.

14. POLYGONS – Introduction
Concave these polygons collapse on themselves. They look like they have a “notch” in them. When I extend the sides, the line cuts through the polygon.
Also, two vertices of the polygon can be connected “outside” of the polygon.

15. POLYGONS – Introduction
Regular Polygons
- convex
- all sides are equal length ( equilateral )
- all angle measures are equal ( equiangular )

16. POLYGONS – Introduction
Regular Polygons
- convex
- all sides are equal length ( equilateral )
- all angle measures are equal ( equiangular )
EXAMPLES :

17. POLYGONS – Introduction
Irregular Polygons
- convex OR concave
- sides are not equal in length
- all angle measures are NOT equal

18. POLYGONS – Introduction
Irregular Polygons
- convex OR concave
- sides are not equal in length
- all angle measures are NOT equal
EXAMPLES :

19. POLYGONS – Introduction
To work with polygons we need to label them. When labeling their vertices, start at one vertice and then move clockwise in consecutive order. Don’t skip letters. A B D C

20. POLYGONS – Introduction
To work with polygons we need to label them. When labeling their vertices, start at one vertice and then move clockwise in consecutive order. Don’t skip letters. A B D C
To name polygons, state their vertices in order.
- polygon ABCD

21. POLYGONS – Introduction
To work with polygons we need to label them. When labeling their vertices, start at one vertice and then move clockwise in consecutive order. Don’t skip letters. A B M D C
To name polygons, state their vertices in order.
- polygon ABCD
- polygon MNO O N

22. POLYGONS – Introduction
Once the polygons are labeled, you can reference the polygons sides and angles. A B M D C O N

23. POLYGONS – Introduction
Once the polygons are labeled, you can reference the polygons sides and angles.
Side AB A B
Angle M M D C O N