SOLUTION: log(d)+log(2d+1)=log(7d) please help!!

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Question 430748: log(d)+log(2d+1)=log(7d)
please help!!
Found 2 solutions by stanbon, vleith:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
log(d)+log(2d+1)=log(7d)
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log[d(2d+1)] = log(7d)
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log[2d^2+d] = log(7d)
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2d^2+d = 7d
2d^2-6d = 0
2d(d-3) = 0
d = 0 or d = 3
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d=0 cannot be a solution because log(0) does not exist.
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So d = 3 is the only solution.
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Cheers,
Stan H.

Answer by vleith(2983) About Me  (Show Source):
You can put this solution on YOUR website!
log(d)+log(2d+1)=log(7d)
log(d*(2d+1)) = log(7d)
Thus d%2A%282d%2B1%29+=+7d
2d%2B1+=+7
2d+=+6
d+=+3