Question

Can someone pls help? ab to fail geometry. any help is nice.

Law of cosines: a2 = b2 + c2 – 2bccos(A)
What is the measure of C to the nearest whole degree?.

Answer 1

By the law of cosines, the angle
`C` satisfies


`8.77^2=2^2+9^2-2*2*9*\cos C`

which reduces to


`\cos C=0.2246\implies C=\arccos(0.2246)\approx1.34422\text{ rad}`

which converts to approximately 77 degrees (this can be done my multiplying by 180 and dividing by pi).