1. Angles

2. Acute Angle An angle that measures between 0 and 90 degrees.

3. Right Angle An angle that measures 90 .

4. Obtuse Angle An angle that measures between 90 and 180 degrees.

5. Straight Angle An angle that measures 180 .

6. Reflex Angle An angle with measure between 180 and 360 degrees.

7. Vertical Angles Two angles across from each other when two lines intersect.

8. Name 2 pairs of vertical angles.  1 &  3  2 &  4

9. Perpendicular Lines Two lines that intersect to form right angles.

10. Adjacent Angles Two angles that share a vertex and ray, but no interior points (don’t overlap).

11. Not Adjacent Angles a b r s Why?

12. Name 4 pairs of adjacent angles.  1 &  2  2 &  3  3 &  4  1 &  4

13. Complementary Angles Two angles with measures that add up to 90°.

14. Find the value of y. y = 90° - 30° =60° y 30 

15. Supplementary Angles Two angles with measures that add up to 180°.

16. Linear Pair of Angles Two adjacent angles that form a line.

17. Find the value of x. x = 180° - 40° = 140°

18. Find x and y. x = 60° y = 180°- 60° y = 120°

19. What would they measure?

21. More Examples: #1 (3x + 2)  xx X = 22

22. Example #2 (3x + 6)  2x  X = 34.8

23. Examples #3  ABC and  CBD form a right angle. m  ABC = 3(m  CBD). How much does each angle measure? m  CBD = 22.5 m  ABC = 67.5

24. Example #4  RST   TSW m  RSW = 95  Each angle measures 47.5 degrees

25. Example #5 RM bisects  LRX. m  LRM = 6x – 9 m  MRX = 3x +12

26. Source http://jwilson.coe.uga.edu/interMath/MainInterMath/Diction ary/ http://access.selkirk.bc.ca/math/Module_4/Mod4_Pt1/mod4_ pt1.html http://www.800score.com/guidetc.html