SOLUTION: Solve: ln (x-5) + ln ( x+4)=ln 36

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Question 303982: Solve: ln (x-5) + ln ( x+4)=ln 36
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Solve: ln (x-5) + ln ( x+4)=ln 36
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ln[(x-5)(x+4)] = ln[36]
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x^2-x-20 = 36
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x^2-x-56 = 0
(x-8)(x+7) = 0
x = 8 or x = -7
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Only x = 8 is an acceptable solution.
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Cheers,
Stan H.
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