consider a triangle where A=30 degrees, a=1.5cm and b=2.8cm
Use the law of sines to find sin(B).

Question

alfie · Answer

Well... it's pretty simple. Just apply the formula...

$$a/sinA = b/sinB$$

To get:

1.5/sin30 = b/sinB.

Now is just an equation.

alfie · Answer

1.5/sin30 = 2.8/sinB 

:)

anonymous · Answer

So would my calculator be best in degrees? If so I got 1.5/sin30 as 3 Is this correct so far?

alfie · Answer

yes... 3 = 2.8/sinb => 3sinb = 2.8 => sinb = 2.8/3 .

anonymous · Answer

sinb=2.8/3 which is .93333333  or .93?

alfie · Answer

sinB = .93333... Now type in the number in your calculator and press "sin" ;).

phi · Answer

I'm sure he means inverse sin

anonymous · Answer

i'm not getting an answer on ti83+ when i enter the .93333 and then hitting sin

anonymous · Answer

inverse sin(.93333) = 68.959 or 68.96

phi · Answer

Looks good.
You can always check:
a/sinA =b/sinB
it should work (it will)

anonymous · Answer

Thank you phi and alfie for all your help. :)