Answer: 47°
Step-by-step explanation:
When given a right angle with 2 lengths and you have to calculate an angle, using Sine, Cosine or Tangent will work best.
Use Sine when given the Opposite and the Hypotenuse lengths.
Use Cosine when given the Adjacent and the Hypotenuse Lengths by and,
Use Tangent when given the Opposite and Adjacent Lengths.
The complete question includes that the side with length 17.6 cm is side BC which means that the side is the Adjacent side.
Cosine will therefore be used.
Cos (B) =
Cos (B) =
Cos (B) = 0.6769
B =
B = 47°