Law of Sines and Cosines Which One?

Find angle A

• 53.6

• 13.3

• 113.1

What is the length of side x?

• 6.57 cm

• 7 cm

• 7.44 cm

• 26.33 cm

How many triangles can you make if m∠A=53, b=6, and a=5?

• 0

• 1

• 2

• Infinitely many

Choose which law you need to solve the problem (DO NOT SOLVE):

• Law of Sines

• Law of Cosines

• Both

• Neither

Which law would you use?

• Law of Sines

• Law of Cosines

Find angle Z

• 20.15°

• 71.23°

• 51.06°

• 57.71°

Find BC

• A

• B

• C

• D

Find the area to the nearest tenth

Solve the Triangle(s): A = 26^o, a = 5, b = 9

• no triangle possible

• B = 14^o, C = 21^o, c = 8.7

• B = 52^o, C = 102^o, c = 11.2

• B = 52^o , C = 102^o, c = 11.2

  OR

  B = 128^o, C = 26^o, c = 5.0

Which of the following formulas shows the Law of Cosines?

• c² = a² + b² - 4ac + cosA

• c² = a² - b² - 2abcosC

• c² = a² + b² - 2abcosC

• (cos A)/a = (cos B)/b