SOLUTION: Hello I need help solving this exponential equation problem: 9^x+1=15. I took the common log of each side like this, x(log9+1log9)=log15 But now I don't know what to do. I don't kn
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-> SOLUTION: Hello I need help solving this exponential equation problem: 9^x+1=15. I took the common log of each side like this, x(log9+1log9)=log15 But now I don't know what to do. I don't kn
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Question 457265: Hello I need help solving this exponential equation problem: 9^x+1=15. I took the common log of each side like this, x(log9+1log9)=log15 But now I don't know what to do. I don't know if this is even the right set up in order to solve this. Does anyone know? Found 2 solutions by stanbon, htmentor:Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! 9^x+1=15
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Note: The log of a sum is not the sum of the logs of the terms.
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Subtract 1 from both sides to get:
9^x = 14
Not take the log:
x*log(9) = log(14)
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x = log(14)/log(9)
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x = 1.2011
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Cheers,
Stan H.
You can put this solution on YOUR website!
The exponent is x+1, so taking the log of both sides gives
(x+1)log 9 = log 15
x = log 15/log 9 - 1
x = 0.2325
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