Question

Can someone help please.

Answer 1

Do you know the Law of sines?

Answer 2

sin a/a=sin b/b= sinc/c ?

Answer 3

you can use it to find angle B

Answer 4

sin(45)/16.5= 22/sin(B)
or (flipping it)
sin(B)/22 = sin(45)/16.5
or multiply both sides by 22
sin(B)= 22*sin(45)/16.5

Answer 5

.94 is what I got?

Answer 6

that is sin(B)= 0.94
take the arcsin (asin or inverse sin) to get the angle.

Answer 7

70.05. got it. thanks.

Answer 8

now angle B' is bigger than 90º (it is obtuse). It is bigger than 90º by the same amount B is less than 90º Does that make sense?

Answer 9

so 90-B= 90-70.05= 19.95
add that to 90 to get B'

Answer 10

this is an ambiguous case. you get two different solution for the same angle. here, if you solve for B' in the triangle at left 9by using sine law), you will get the same result for B' i.e. 70.05..

Answer 11

however, looking at the triangle you can guess whether it is acute or obtuse.