Exercises: Apply the Law of Sines and the Law of Cosines

In triangle $ABC$, all three sides are known: $a = 5$, $b = 7$, $c = 9$. Use the Law of Cosines to find angle $C$ (the largest angle, opposite side $c$). Use $\cos^{-1}(-0.100) \approx 95.7\degree$. Round to the nearest tenth of a degree.