Solve for r
r=-\log_{321}\left(14\right)\approx -0.457261414
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\frac{\frac{3}{7}}{6}=321^{r}
Divide both sides by 6.
\frac{3}{7\times 6}=321^{r}
Express \frac{\frac{3}{7}}{6} as a single fraction.
\frac{3}{42}=321^{r}
Multiply 7 and 6 to get 42.
\frac{1}{14}=321^{r}
Reduce the fraction \frac{3}{42} to lowest terms by extracting and canceling out 3.
321^{r}=\frac{1}{14}
Swap sides so that all variable terms are on the left hand side.
\log(321^{r})=\log(\frac{1}{14})
Take the logarithm of both sides of the equation.
r\log(321)=\log(\frac{1}{14})
The logarithm of a number raised to a power is the power times the logarithm of the number.
r=\frac{\log(\frac{1}{14})}{\log(321)}
Divide both sides by \log(321).
r=\log_{321}\left(\frac{1}{14}\right)
By the change-of-base formula \frac{\log(a)}{\log(b)}=\log_{b}\left(a\right).
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