I am not sure how to solve this question:

cos(x) = 0.873

I am supposed to find all of the angles in the interval [0, 360] that satisfy the equation above. (Round approximations to the nearest tenth of a degree.)

cos x = .873

Take the arccos to find x

So

arccos (.873) = x ≈ 29.2°

The other angle will be [ 360 - 29.2] ≈ 330.8°