SOLUTION: (1/3)^x=(81)(9^(x-1)) when solving for x is -2/3. I do not know how.

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Question 622138: (1/3)^x=(81)(9^(x-1)) when solving for x is -2/3. I do not know how.
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
(1/3)^x=(81)(9^(x-1)) when solving for x is -2/3. I do not know how.
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(1/3)^x=(81)(9^(x-1))
1/(3^x)=(81)(3^2)^(x-1)
3^-x/(81)(3^(2x-2))
3^-x/(3^(2x-2))=81
3^(-3x+2)=3^4
-3x+2=4
-3x=2
x=-2/3
note: when moving from denominator to numerator or vise-versa, sign of exponents change.