1. Exploring

2.  Polygons are many-sided figures, with sides that are line segments.  Polygons are named according to the number of sides and angles they have.

5.  Can be “regular” – all sides and all angles are equal to each other. Regular or irregular?

6.  Try to draw it in your notebook.  Talk and Turn to discover whether this is possible or not. Why or why not?

7.  TRIANGLES!

8.  Two sides of equal length  Three acute angles  Sum of angles = 180°

9.  Teacher: When I say, isosceles, you say 2 sides equal! Isosceles!  Students: 2 sides equal!

10.  All sides equal length  Three acute angles  Sum of angles = 180°  Is a regular polygon

11.  Teacher: When I say, equilateral, you say all sides equal! Equilateral!  Students: all sides equal!

12.  No sides are equal  No angles are equal  May have obtuse angle  Sum of angles = 180 °

13.  Teacher: When I say, scalene, you say NO sides equal! Scalene!  Students: NO sides equal!

14.  By their angles!!

15.  Has 1 right angle!  90 degrees  The little square box in the corner

16.  Can you make a triangle with 2 right angles? Why or why not?

17.  Triangle with all angles LESS than 90 degrees.  The curve shows that it is an acute angle.  ALL triangles have some acute angles.  An acute triangle is special, because it has ALL acute angles.

18.  A triangle with one obtuse angle (more than 90 degrees)  Talk and Turn: can you make a triangle with more than one obtuse angle? Why or why not?

19.  4 sides  4 angles  QUAD = 4

20.  There are many types of SPECIAL quadrilaterals

21.  Opposite sides are parallel  Opposite side are equal in length  Each angle equals 90°  Sum of angles = 360°

22.  All sides equal  All angles equal and are 90 ° each  Sum of angles = 360 °  Is a regular polygon

23.  Two sides are parallel  Has obtuse and acute angles  Sometimes has a right angle  Sum of angles = 360 °

24.  All four sides of equal length  Opposite angles are equal – 2 acute angles, 2 obtuse angles  Sum of angles = 360 °  Regular polygon

25.  Opposite sides parallel  Opposite sides equal in length  Opposite angles equal  Sum of angles = 360 °

26.  http://www.schooltube.com/video/2020fa2f64 2304cf32e4/Polygon- Song http://www.schooltube.com/video/2020fa2f64 2304cf32e4/Polygon- Song

27.  5 sides  Sum of angles = 540 °  Regular polygon

28.  6 sides  Sum of angles = 720 °  Can be regular polygon

29.  8 sides  Sum of angles = 1080 °  Can be regular polygon

30.  9 sided polygon  9 angles

31.  10 sides  Sum of angles = 1440°  Can be regular polygon