Hi I'm learning the Laws of Sine and I don't understand part of it.
7.7/sin 43.2 degrees = 9.1/sin B → sin B = 9.1 (sin 43.2 degrees)/7.7 = 0.8090 → B = 54° or B = 180° - 54° = 126° (to the nearest tenth). How do they go from 0.8090 to B=54.

Question

Hi I'm learning the Laws of Sine and I don't understand part of it.
7.7/sin 43.2 degrees = 9.1/sin B → sin B = 9.1 (sin 43.2 degrees)/7.7 = 0.8090 → B = 54° or B = 180° - 54° = 126° (to the nearest tenth). How do they go from 0.8090 to B=54.

anonymous · Answer

I feel like it's simple but I can't remember.

luffingsails · Answer

Law of Sines: a/sin A = b/sin B = c/sin C
Right?

anonymous · Answer

yes

luffingsails · Answer

Okay, just checking. lol
Can you use a calculator?

luffingsails · Answer

for the problem, I mean.

anonymous · Answer

Yea I can

anonymous · Answer

Well that's just it I'm not sure what I'm supposed to be calculating

luffingsails · Answer

Okay, so they finish with 
sin B = 9.1 (sin 43.2 degrees)/7.7 = 0.8090
Take the inverse sine of .8090

anonymous · Answer

Oh that makes so much more sense thanks I get it now.

luffingsails · Answer

Sure. glad to help.