Thanks guys, however, for my assignment I need to use the law of sinus as well as cosinus, so I try to figure out the angles by using the law of sinus.
But I think I got it figured out now, so thanks, saved my ass there. :P
I don't see why you would law of sines. It is incorrect to use law of sines because you run into the scenario where sinA=x. Therefore solving for A would be arcsin(x) or 180-arcsin(x). The sketch would make it obvious what the correct choice is, however it's wrong to use this method. If you are required to use only law of sines and cosines, use law of cosines a third time rather than sum of angles. C = arcos[(a^2 + b^2 - c^2)/2ab]
You find cos(a)=0.794207, then A=37.42°
(a/sin(a))=(b/sin(b)) you get
No idea what this guy is talking about to be honest. Go ahead and use the law of sines.
Also I don't know why he's saying not to use the sum of the angles when he used it himself in his earlier post lol...
Anyway you have the answer, just be mindful that you're actually solving for the angle you're doing the work for.
Firstly, I quoted that the OP claimed that the assignment stated to use law of sines and law of cosines. I was pointing out that the problem didn't need to use the sum of the angles if the problem statement forbids it which is how I understood the OP's response.
An example of why using sines would have been bad.
If you run into solving for an angle using law of sines you would get something that looks like A = arcsin(.5), obviously these are not the numbers from the problem.
lets solve this, throw it in the calculator or what have you, calculator does magic, and.... it tells you A =30. Wait a second, lets try and go the other way and confirm this by doing sin(30)=A. This yields A= .5 just like it should. But check this out, sin(150)=.5
This is why using law of sines can be dangerous, for any angles located between 0 and 180, cosines is better to use.