1. Good Morning, Precalculus! To prepare for class: 1. Please find your DO NOW sheet and start today's DO NOW! Do Now: 1) Check to make sure your calculator is in degree mode [it is if sin(30) = 0.5] 2) Solve the proportion by cross-multiplying and using your calculator:

2. Do Now: 1) Check to make sure your calculator is in degree mode [it is if sin(30) = 0.5] 2) Solve the proportion by cross-multiplying and using your calculator:

3. Upcoming Assignments Due Thursday, 3/14: Half-sheet of practice problems

4. Today's Objective Unit 10, Objective 1: I will be able to use the Law of Sines and the Law of Cosines to solve for missing sides and angles in triangles. Section 5-6, pgs. 313-318 Section 5-8, pgs.327-332

5. Today's Agenda: 1. Do Now 2. Today's Objective 3. The Law of Sines 4. The Law of Cosines 5. Practicing with Whiteboards

6. 1) Triangle Angle Sum Theorem (angles add to 180 deg.) 2) Pythagorean Thm. a2 + b2 = c2 3)Sin 4)Cos 5)Tan 6)Sin-1 7)Cos-1 8)Tan-1 54o xo 114o

7. 1) Triangle Angle Sum Theorem (angles add to 180 deg.) 2) Pythagorean Thm. a2 + b2 = c2 3)Sin 4)Cos 5)Tan 6)Sin-1 7)Cos-1 8)Tan-1 13 x 12

8. 1) Triangle Angle Sum Theorem (angles add to 180 deg.) 2) Pythagorean Thm. a2 + b2 = c2 3)Sin 4)Cos 5)Tan 6)Sin-1 7)Cos-1 8)Tan-1 x 3 4

9. 1) Triangle Angle Sum Theorem (angles add to 180 deg.) 2) Pythagorean Thm. a2 + b2 = c2 3)Sin 4)Cos 5)Tan 6)Sin-1 7)Cos-1 8)Tan-1 x 51o 15 HYPOTENUSE OPPOSITE ADJACENT

10. 1) Triangle Angle Sum Theorem (angles add to 180 deg.) 2) Pythagorean Thm. a2 + b2 = c2 3)Sin 4)Cos 5)Tan 6)Sin-1 7)Cos-1 8)Tan-1 x 51o 12 HYPOTENUSE OPPOSITE ADJACENT

11. 1) Triangle Angle Sum Theorem (angles add to 180 deg.) 2) Pythagorean Thm. a2 + b2 = c2 3)Sin 4)Cos 5)Tan 6)Sin-1 7)Cos-1 8)Tan-1 x 51o 15 HYPOTENUSE OPPOSITE ADJACENT

12. 1) Triangle Angle Sum Theorem (angles add to 180 deg.) 2) Pythagorean Thm. a2 + b2 = c2 3)Sin 4)Cos 5)Tan 6)Sin-1 7)Cos-1 8)Tan-1 25 xo 16 HYPOTENUSE OPPOSITE ADJACENT

13. 1) Triangle Angle Sum Theorem (angles add to 180 deg.) 2) Pythagorean Thm. a2 + b2 = c2 3)Sin 4)Cos 5)Tan 6)Sin-1 7)Cos-1 8)Tan-1 26 xo 10 HYPOTENUSE OPPOSITE ADJACENT

14. 1) Triangle Angle Sum Theorem (angles add to 180 deg.) 2) Pythagorean Thm. a2 + b2 = c2 3)Sin 4)Cos 5)Tan 6)Sin-1 7)Cos-1 8)Tan-1 xo 18 24 HYPOTENUSE OPPOSITE ADJACENT

15. 1) Triangle Angle Sum Theorem (angles add to 180 deg.) 2) Pythagorean Thm. a2 + b2 = c2 3)Sin 4)Cos 5)Tan 6)Sin-1 7)Cos-1 8)Tan-1 xo 38o 16 26 ?

16. 1) Triangle Angle Sum Theorem (angles add to 180 deg.) 2) Pythagorean Thm. a2 + b2 = c2 3)Sin 4)Cos 5)Tan 6)Sin-1 7)Cos-1 8)Tan-1 120o 48o x ? 24

17. The Law of Sines

18. Deriving the Law of Sines

26. The Law of Cosines

30. 9

32. Practicing with Whiteboards

33. 580 6 x 15 Law of Sines? Law of Cosines? Neither?

34. Law of Sines? Law of Cosines? Neither?

35. 9 x 9 Law of Sines? Law of Cosines? Neither?

36. Law of Sines? Law of Cosines? Neither? 1340

37. Law of Sines? Law of Cosines? Neither?

38. Law of Sines? Law of Cosines? Neither?