SOLUTION: solve for x 12^(-7x)=7^(-x+8) give the exact answer using base 10 logarithms

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Question 482670: solve for x
12^(-7x)=7^(-x+8)
give the exact answer using base 10 logarithms
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
solve for x
12^(-7x)=7^(-x+8)
give the exact answer using base 10 logarithms
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-7x*log(12) = (-x+8)*log7
----
-7*log(12) = -x*log(7) + 8*log(7)
(-7log(12)+log(7)]x = 8*log(7)
----
x = -0.1260
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Cheers,
Stan H.