Answer
$x^{m}=3$
Work Step by Step
For $x\gt 0$ and $a$, a positive constant other than 1,
$\log_{a}x$ is the exponent to which $a$ must be raised in order to get $x$.
Thus, $\log_{a}x=m$ means $a^{m}=x$
Here, $\log_{x}3=m$ means $x^{m}=3$