2. Polygons

3. Polygons are many-sided closed figures, with sides that are line segments. Polygons are named according to the number of sides and angles they have. Can be “regular” – all sides and all angles are equal to each other

4. Q: Is this a polygon? Why or why not? A: No… Polygons are closed figures.

5. Q: Is this a polygon? Why or why not? A: No… It is not made of line segments.

6. A triangle has three sides triangle

7. A square has four sides triangle

8. A Pentagon has five sides triangle

9. A hexagon has six sides triangle

10. A Octagon has eight sides triangle

11. Let’s Review: The triangle is the smallest polygon. It only has three sides. A pentagon has five sides. A hexagon has six sides. A heptagon has seven sides. An octagon has eight sides.

12. Match these. Triangle eight sides Heptagon three sides Octagonseven sides

13. Match some more. Pentagon four sides Hexagonfive sides Squaresix sides

14. Find the polygon… Click on the polygon.

15. Sorry… Polygons are closed shapes. They cannot have breaks or openings.

16. Polygons only have straight sides. They can’t have curves or be circles. Sorry…

17. Congratulations! Polygons are closed shapes (no holes) with straight sides. All triangles are polygons.

18. u A triangle is the smallest polygon because it has three sides. Can you have a two- sided polygon? Why or why not? Two lines don’t close to make a shape. They make an angle. 2 1 Key Question:

19. Polygons with 3 sides… Triangles Polygons with 4 sides… Quadrilaterals Polygons with 5 sides.. Pentagons But wait we have more polygons Polygons with 6 sides… Hexagons Polygons with 7 sides… Heptagons Polygons with 8 sides… Octagons But still we have more polygons Polygons with 9 sides… Nonagons Polygons with 10 sides… Decagons Polygons with 12 sides… Dodecagons And now we have our polygons Hip Bone’s connected to the… Classifying Polygons Song