hi:) for 5(b) , I got 157.7 & 22.3 but in the answer key, the only correct answer is 157.7. I thought there should be 2 possible values?

Answer:
Θ = 157.7°
Step-by-step explanation:
Given
cosΘ = - 0.925
Since cosΘ < 0 then Θ is in the second or third quadrant.
Since 0° ≤ Θ ≤ 180° then Θ is in the second quadrant. thus
Θ = [tex]cos^{-1}[/tex](- 0.925) = 157.7° ← angle in second quadrant
Answer:
There should be only 1 value (157.7°) since we reject the second value as θ lies in quadrant 1 and 2. Note that the 2nd value should have been 202.3°, which is greater than 180°.
Cosine of an angle negative in the 2nd and 3rd quadrant.
Step-by-step explanation:
Please see attached picture.