Answer:
B = 54 to the nearest degree.
Explanation:
Remark
This is a sine law question. They can be rather nasty because no answer or 2 answers are possible. This one is well behaved because B, you are told, is acute. The two answer kind needs the supplement of an acute angle.
Sorry this blabs on and shouldn't. You are looking for <B
Formula
Sin(<B)/the side opposite = Sin(<A) / side opposite it
Simplified
Sin(<B) / 9 = Sin(A)/11
Sin(<B) / 9 = Sin(80) / 11 Multiply both sides by 9
9*Sin(B) / 9 = 9 * Sin(80) /11 The 9s Cancel
Now all you need to do is put it in your calculator. Do you need the steps?
Sin(B) = 9*sin(80) / 11
Sin(B) = 9 * 0.9848 /11
Sin(B)= 0.8058
B = Sin-1(0.8058)
B = 53.68
B = 54