Solve for x_3
x_{3}=-3
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3^{x_{3}}=\frac{1}{27}
Use the rules of exponents and logarithms to solve the equation.
\log(3^{x_{3}})=\log(\frac{1}{27})
Take the logarithm of both sides of the equation.
x_{3}\log(3)=\log(\frac{1}{27})
The logarithm of a number raised to a power is the power times the logarithm of the number.
x_{3}=\frac{\log(\frac{1}{27})}{\log(3)}
Divide both sides by \log(3).
x_{3}=\log_{3}\left(\frac{1}{27}\right)
By the change-of-base formula \frac{\log(a)}{\log(b)}=\log_{b}\left(a\right).
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