SOLUTION: Should the triangle be solved beginning with Laws of Sines or Laws of Cosines. Then solve the triangle and round to the nearest tenth. A=16, b=13, c=10. Thank You

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Question 44208: Should the triangle be solved beginning with Laws of Sines or Laws of Cosines. Then solve the triangle and round to the nearest tenth. A=16, b=13, c=10.
Thank You
Answer by adamchapman(301) About Me  (Show Source):
You can put this solution on YOUR website!
The sine rule a%2FsinA=b%2FsinB=c%2FsinC can only be used effectively when you know an angle and the length opposite that angle and one other property (length or angle). Since we don't have this infromation, we have to use the cosine rule a%5E2=b%5E2%2Bc%5E2%2B2bc%2AcosA
This gives us a=22.8 to the nearest tenth.
Now we can use the sine rule:
22.78%2Fsin16=13%2FsinB=10%2FsinC%29
This solves to give B=arcsin%2813%2F22.78%29=34.8
All the angles in any triangle add up to 180 degrees.
A%2BB%2BC=180
16%2B34.8%2BC=180
C=129.2degrees.
I hope this helps
P.S. I am trying to start up my own homework help website. I would be extremely grateful if you would e-mail me some feedback on the help you received to adam.chapman@student.manchester.ac.uk