laws of cosines!!! find C round to the nearest tenth!!!! someone help

Answer:
[tex] C = 69.1^\circ [/tex]
Step-by-step explanation:
[tex] c^2 = a^2 + b^2 - 2ab\cos C [/tex]
[tex] a = 17 ft; ~b = 8 ft; ~c = 16 ft [/tex]
[tex] 16^2 = 17^2 + 8^2 - 2(17)(8)\cos C [/tex]
[tex] 256 = 289 + 64 - 272\cos C [/tex]
[tex] -97 = -272 \cos C [/tex]
[tex] \cos C = \dfrac{-97}{-272} [/tex]
[tex] \cos C = 0.3566 [/tex]
[tex] C = \cos^{-1} 0.3566 [/tex]
[tex] C = 69.1^\circ [/tex]