1. 1.6 Measuring Angles To Find the Measures of Angles To Identify Special Angle Pairs

2. What is an Angle?

3. Naming an Angle… We can name this Angle… By its vertex: < B (Angle B) By using three points: < TBQ (Angle TBQ) < QBT (Angle QBT) By a Number: < 1 (Angle One)

4. Naming Angles Name <1 in two other ways. < AEC <CEA Name <CED in two other ways. < 2 <DEC Can we name any of the angles <E? Why or Why not?

5. Example 1A a.Give Two other names for <ABD. b.Which 3 Angles have D as their Vertex?

6. Example 1B c.Does <3 and <Z name the same Angle? Explain. d.List all the angles that have W as a Vertex.

7. Classifying Angles by their Measures

9. Congruent Angles…

10. Angle Addition Postulate…

11. Ex 2: Using the Angle Addition Postulate a.What is m<TSW if m<RST = 50 and m<RSW = 125?

12. Ex 2B: Try one… If m<DEG = 145, find m<GEF. (Remember m<DEF=180 because it’s a Straight Angle)

13. Ex 3: Some More Algebra… c.In the figure, ray XP and ray XT are opposite rays and ray XQ bisects <PXS. For each situation, find the value of x and the measure of the indicated angle.

14. Ex 3: Some More Algebra… d.Find m<RXS.

15. Identifying Angle Pairs…

16. Example 4 Tell whether each pair of angles are only adjacent, adjacent and form a linear pair, or not adjacent. a.<AEB and <BED b.<AEB and <BEC c.<DEC and <AEB

17. Identifying Angle Pairs…

19. Ex 5: Identify Angle Pairs

20. Ex 6: Find The Measure… Find: a) complement of <F b) supplement of <F

21. Ex 7: Find x!

22. What can I assume from a diagram? If you are given a diagram, there are some ideas we can conclude just by looking at it. You can conclude that angles are: Adjacent Adjacent Supplementary Vertical Straight

23. What can’t I assume from a Diagram? Unless there are marks or symbols indicated in the diagram, you cannot assume that: Angles or segments are congruent Angles are Right or 90 degrees Lines are Parallel or Perpendicular

24. Make Conclusions…

25. Ex 8: Can you make these conclusions?

26. Closure… How are angles classified? What are the special Angle pairs?