Solving for Distance using Law of Cosines

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The discussion revolves around a navigation problem involving a ship changing course to avoid icebergs, requiring the use of the Law of Cosines and Law of Sines to calculate distances. The user initially struggles with the Law of Cosines due to having only one known side and expresses frustration with the complexity of the equations. After some deliberation, they discover that the Law of Sines is applicable and successfully solve the problem. The user humorously criticizes their professor for earlier advice against using the Law of Sines. Ultimately, the discussion highlights the importance of flexibility in choosing mathematical methods for problem-solving.
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Homework Statement


A ship sailing due east in the North Atlantic has been warned to change course to avoid a group of icebergs. The captain turns at point A and sails on a bearing of 62° for a while, then changes course again at point C to a bearing of 115° until the ship reaches its original course at point B. The distance between point A and B is 50 miles. How much farther did the ship have to travel to avoid the icebergs?

Homework Equations


a2 = b2 + c2 - 2bc*cosA
b2 = a2 + c2 - 2ac*cosB
c2 = a2 + b2 - 2ab*cosC

a/sinA = b/sinB = c/sin C

The Attempt at a Solution


I figured out all of the angles, but I only have one side, and I can't get the numbers to work in any of the law of cosines equations. I don't know if I should try law of sines, because my professor told me not to use law of sines with any angles greater than 90°. I think making a system of equations in this problem would be too complicated, I'm sure there's an easier way somewhere. Help please?
 

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Oh! Nevermind, law of sines worked just fine. My professor is a poopyhead!
 
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