document.write( "Question 820009: Use the Law of Cosines to fi nd angle C if side a= 20, side b= 25 and side c= 22 \n" ); document.write( "
Algebra.Com's Answer #493372 by ortarico(23)\"\" \"About 
You can put this solution on YOUR website!
You didn't state the range of titha but I'll leave my answer with the value for Acute.
\n" ); document.write( "a = 20
\n" ); document.write( "b = 25
\n" ); document.write( "c = 22
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\n" ); document.write( "\n" ); document.write( "Cos C = (a^2 b^2 - c^2/2ab
\n" ); document.write( "Cos C = (20^2 25^2 - 22^2)/2(20)(25)
\n" ); document.write( "Cos C = (400 625 - 484)/1000
\n" ); document.write( "Cos C = 541/1000
\n" ); document.write( "Cos C = 0.541
\n" ); document.write( "C = ARC(COS) 0.541
\n" ); document.write( "C = 57.25deg
\n" ); document.write( " \n" ); document.write( "
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