1. + Objective: Bisect and angle DO NOW: p. 60 in textbook (Folding Angle Bisectors) HOMEWORK: 1.2.2 Practice Worksheet A 2.Open notes vocabulary quiz tomorrow (2.1-2.3) DATE Oct. 6, 2014

2. + Homework Check 1. Yes (tic marks) 2. No (no tic marks) 3. No (its an endpoint) 4. PM = 11; MD = 11 5. TM = 7.5; MS = 7.5 6. AM = 9.2; AB = 18.4 7. FG = 17; EG = 34 8. x = 3 9. x = 5 10. (1, 1) 11. (2.5, -4) 12. (-4, 4) 13. (3.5, -3) 14. (2, 2.5) 15. (-2, 4) 16. 5.5 ft 2.1 B

3. + IMPORTANT TERMS Angle bisector: An angle bisector is a ray that divides an angle into two angles that are congruent.

4. + Example 1 BD bisects LABC, and mLABC = 110 o Find mLABD and mLDBC Find angle measures

5. + Solution BD bisects LABC, so mLABC is half of mLABC. mLABD Example 1

6. + Check Point HK bisects LGHJ. Find mLGHK and mLKHL. 1. mLGHK = mLKHL = 2. mLGHK = mLKHL = 3. mLGHK = mLKHL =

7. + Solutions 1. mLGHK = 16 o mLKHL = 16 o 2. mLGHK = 45 o mLKHL = 45 o 3. mLGHK = 80.5 o mLKHL = 80.5 o Checkpoint

8. + Example 2 Angle Measures and Classification

9. + Solutions Example 2

10. + Checkpoint 4. mLSQP = mLPQR = 5. mLSQP = mLPQR = 6. mLSQP = mLPQR =

11. + Solutions 4. mLSQP = 29 o mLPQR = 58 o acute 5. mLSQP = 45 o mLPQR = 120 o right 6. mLSQP = 60 o mLPQR = 120 o obtuse Checkpoint

12. + Example 3 Use Algebra with Angle Measures

13. + Solutions Example 3

14. + Follow up Substitute your value of x in the original equation to determine whether it is a solution. ???

15. + Checkpoint BD bisects LABC. Find the value of x.

16. + Solution 7. 43 8. 3 Checkpoint

17. + Closing Exit Card: Find the segment length. THEN place a +, check, or – for understanding of today’s lesson! USE THE MIDPOINT FORMULA: R(5,6) P(-3, 0)