SOLUTION: (r-3)(r+15)=-33

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Question 613382: (r-3)(r+15)=-33
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
(r-3)(r+15)=-33
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r^2+15r-3r-45 = -33
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r^2 + 12r -12 = 0
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r = [-12 +- sqrt(144-4*-12)]/2
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r = [-12 +- sqrt(192)]/2
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r = [-12 +- 8sqrt(3)]/2
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r = [-6+-4sqrt(3)]
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Cheers,
Stan H.
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