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SAFind the value of x.Round to the nearest tenth.X29B50x = [? ]°26C

SAFind the value of x.Round to the nearest tenth.X29B50x = [? ]°26C-example-1
User Sanyam Goel
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1 Answer

17 votes
17 votes

Law of cosines:


c^2=a^2+b^2-2ab\cos C

For the given triangle:


\begin{gathered} a=26 \\ b=50 \\ c=29 \\ A=x \\ \\ a^2=b^2+c^2-2bc\cos A \end{gathered}
26^2=50^2+29^2-2(50)(29)\cos x

Solve x from the equation above:


\begin{gathered} 676=2500+841-2900\cos x \\ 676=3341-2900\cos x \\ 676-3341=-2900\cos x \\ -2665=-2900\cos x \\ (-2665)/(-2900)=\cos x \\ \\ \cos x=(533)/(580) \\ \\ x=\cos^(-1)((533)/(580)) \\ \\ x\approx23.2 \end{gathered}Then, the value of x is 23.2º
User Rick Lancee
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