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March 13th, 2008, 02:40 PM  #1 
Newbie Joined: Mar 2008 Posts: 6 Thanks: 0  Triangle side lengths 
March 13th, 2008, 03:39 PM  #2 
Global Moderator Joined: May 2007 Posts: 6,528 Thanks: 589  Re: Triangle side lengths Let c=x use the law of cosines c^2=a^2+b^22abcosC In your case a=15, b=16, C=58 deg are known. Assuming the angles are correct you could also use the law of sines a/sinA =c/sinC where A=64 deg. If you don't get the same c both ways, then the data given is incorrect. 
March 13th, 2008, 07:25 PM  #3 
Global Moderator Joined: Dec 2006 Posts: 19,063 Thanks: 1621 
It's pretty obvious that the given measurements are inconsistent. The third angle would be 58°, making the triangle isosceles and hence x equal to 16. That's nonsense, since the shortest side can't be opposite the greatest angle.


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lengths, side, triangle 
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