SOLUTION: 4^(2x)=5^(x-2) Solve and check for extraneous solution.

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Question 1059908: 4^(2x)=5^(x-2) Solve and check for extraneous solution.
Found 2 solutions by stanbon, Alan3354:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
4^(2x)=5^(x-2) Solve and check for extraneous solution.
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(2x)*log(4) = (x-2)*log(5)
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[2x/(x-2)] = = log(5)/log(4)
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[2x/(x-2)] = 1.161
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2x = 1.161x -2.322
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0.839x = -2.322
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x = -2.768
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Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
4^(2x)=5^(x-2)
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2x*log(4) = (x-2)*log(5) = x*log(5) - log(25)
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x*log(16) - x*log(5) = -log(25)
x*(log(16) - log(5)) = -log(25)
x = log(25)/(log(5) - log(16))
x = log(25)/log(5/16)
x = ~ -2.767376