Question 1041851
I would like your help on the following problem:
Solve for θ (in degrees) if 1-8*cosθ=6 and 0 is greater than or equal to θ but less than 360°.

I understand to move everything to the other side in order to get cosθ by itself and I end up with cosθ=5/-8 but that is not the answer and I am not entirely sure of what the next step is.
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cos = -5/8 = -0.625
From a calculator:
theta =~ 128.68 degs
=~ 231.32 degs