Question

!! HELP PLEASE!!

6. Solve the triangle below.

Part I: Use the law of cosines to find the measure of angle B. (2 points)​

Answer 1

Here

• a=22
• b=21
• c=16

Apply law of cosines

`\ \ \sf\longmapsto cosB=(a^2+b^2+c^2)/(2ac)`

`\ \ \sf\longmapsto cosB=(22^2+21^2+16^2)/(2(22)(16))`

`\ \ \sf\longmapsto cosB=(484+441+256)/(704)`

`\ \ \sf\longmapsto cosB=(1181)/(704)`

`\ \ \sf\longmapsto cosB=0.42`

`\ \ \sf\longmapsto B=cos^(-1)(0.42)`

`\ \ \sf\longmapsto B=64.8°`

Answer 2

• 64.86°

Explanation:

Use the law of cosines:

• cos ∠B = (a² + c² - b²) / (2ac)
• cos ∠B = (16² + 22² - 21²) / (2*16*22)
• cos ∠B = 0.4247
• m∠B = arccos 0.4247
• m∠B = 64.86° (rounded to the nearest hundredths)