SOLUTION: 9 cos x + 5 = −cos x

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Question 1112525: 9 cos x + 5 = −cos x
Answer by stanbon(75887)   (Show Source): You can put this solution on YOUR website!
9 cos x + 5 = −cos x
10cos(x) = -5
cos(x) = -1/2
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x = arccos(-1/2) = 2pi/3
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Cheers,
Stan H.
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