Answer:
(28) B = 60°
(30) C = 8.00°
Explanation:
- Both problems require us to use inverse trigonometry to find the measures of angles B and C.
(28) Step 1:
cos (reference angle) = adjacent/hypotenuse and we normally use it to find side lengths.
- Using the inverse cosine equation, cos^-1 (adjacent/hypotenuse) = angle, allows to find the measure (m) of B:
cos^-1 (0.5000) = m angle B
cos ^-1 (0.5000) = 60°
Thus the measure of B is 60°
(30) Step 1:
tan (reference angle) = opposite/adjacent and we normally use it to find side lengths as well.
- Using the inverse tangent equation, tan^-1 (opposite/adjacent) = angle, allows us to find the measure of C:
tan^-1 (0.1405) = m angle C
tan^-1 (0.1405) = 7.997705648
tan^-1 (0.1405) = 8.00°
Thus, the measure of C is approximately 8.00°
- As long as you follow the steps I provided your teacher/instructor will hopefully accept C = 8.00° as an answer even though it's rounded
- You're also free to use the unrounded and more exact answer C = 7.997705648°