Answer
$log_{13}x=2$
Work Step by Step
From the definition of the logarithmic function on page 456, we know that $b^{y}=x$ is equivalent to $y=log_{b}x$ (for $x\gt0$, $b\gt0$, and $b\ne1$).
Therefore, $13^{2}=x$ is equivalent to $log_{13}x=2$ in logarithmic form.