Given problem type SAA or ASA, how would you solve for the length of any of the remaining sides?

A. Use the fact that the angles add up to 180 degrees, and then use the law of cosines.
B. Use the fact that the angles add up to 180 degrees, and then use the law of tangents.
C. Use the fact that the angles add up to 180 degrees, and then use the triangle inequality theorem.
D. Use the fact that the angles add up to 180 degrees, and then use the law of sines.
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Question

Given problem type SAA or ASA, how would you solve for the length of any of the remaining sides?



 		A.	Use the fact that the angles add up to 180 degrees, and then use the law of cosines.
 		B.	Use the fact that the angles add up to 180 degrees, and then use the law of tangents.
 		C.	Use the fact that the angles add up to 180 degrees, and then use the triangle inequality theorem.
 		D.	Use the fact that the angles add up to 180 degrees, and then use the law of sines.
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mathmate · Answer

Hints:
If you know the length of any two sides and the included angle, you can use the cosine rule.  Do that whenever you can. Otherwise....
if you know the length of only one side of a triangle, or two sides but NOT the included angle, use the law of sines.  

If you are solving for an angle, look for possible obtuse angles when using the sine rule.