1. Sine Rule and Cosine Rule Clicker Practice

2. SOH/CAH/TOA can only be used for right-angled triangles. The Sine Rule can be used for any triangle: AB C a b c The sides are labelled to match their opposite angles a sinA b sinB c sinC= The Sine Rule:

3. We use the Sine Rule when: We have two angles and a side OR We have two sides and the non-included angle (this is the ambiguous case)

4. Practice Together: find the length of h in mm. G H I 41 º 76 º 26 mm Degree mode!!

5. Find the length of a in cm. 5.530 A B C 62 º 53 º 5 cm 3 sig figs!!

6. Find the length of f in cm. 6.360 D EF 28 º 130 º 13 cm 3 sig figs!!

7. Practice Together: Find the measure of angle ABC. 47 º 6 cm 5 cm A B C θ

8. Find the measure of angle PRQ: 51.10.1 27 º 6 km 3.5 km 3 sig figs!! P Q R θ

9. Find the measure of angle EDF: 57.70 8 m 70 º 9.5 m D E F θ 3 sig figs!!

10. We use the Cosine Rule when: Two sides and the INCLUDED angle (SAS) OR All three sides (SSS)

11. The Cosine Rule C B c a b BB AA CC (One side) 2 = (other side) 2 +(last side) 2 - 2(other side)(last side)cos(angle of 1 st side)

12. Practice Together: Find the length of side a

13. Find the length of side r in km: 3.380 3 sig figs!!

14. Find the length of AC in cm: 8.390 3 sig figs!! A B C 72 º 5.4 cm 8.3 cm

15. Practice Together: Find the measure of the unknown angles

16. Find the measure of angle GHI 68.70 G H I θ 12 cm 11 cm 13 cm 3 sig figs!!

17. Find the measure of angle DEF: 1120 3 sig figs!! D E F 10 cm 7 cm 5 cm

18. Find the measure of the largest angle of a triangle with sides 11cm, 13cm, and 19cm. 1040 3 sig figs!!