Solve for x
x=7
Solve for x (complex solution)
x=-\frac{i\pi n_{1}}{\ln(3)}+7
n_{1}\in \mathrm{Z}
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9^{-x+9}=81
Use the rules of exponents and logarithms to solve the equation.
\log(9^{-x+9})=\log(81)
Take the logarithm of both sides of the equation.
\left(-x+9\right)\log(9)=\log(81)
The logarithm of a number raised to a power is the power times the logarithm of the number.
-x+9=\frac{\log(81)}{\log(9)}
Divide both sides by \log(9).
-x+9=\log_{9}\left(81\right)
By the change-of-base formula \frac{\log(a)}{\log(b)}=\log_{b}\left(a\right).
-x=2-9
Subtract 9 from both sides of the equation.
x=-\frac{7}{-1}
Divide both sides by -1.
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