2. 5.8 The Law of Cosines

3. Law of Cosines – Law of Cosines allows us to solve a triangle when the Law of Sines cannot be used. Most problems can be solved in more than one way. Choosing the most efficient way to solve a problem is sometimes not obvious. Decision making is an important problem-solving strategy

4. Law of Cosines – Law of Cosines allows us to solve a triangle when the Law of Sines cannot be used. Most problems can be solved in more than one way. Choosing the most efficient way to solve a problem is sometimes not obvious. Decision making is an important problem-solving strategy

5. The Law of Cosines can be used to solve a triangle in the following cases Case 1. You know the measures of 2 sides and the included angle. Case 2. You know the measures of three sides.

7. Solve the triangle. Ex: A = 120, b = 9, c = 5

8. Solve the triangle Ex: a = 24, b = 40, c = 18

9. Find the area a = 4, b = 7, c = 9

10. Hero’s Formula

11. Find the Area a = 72, b = 83, c = 95