Answer
$b^y=x$
Work Step by Step
RECALL:
$y=\log_b{x} \longleftrightarrow b^y=x$ where $x \gt 0$, $b\gt 0, b\ne1$
Therefore, the missing expression is $\underline{b^y=x}$.
You can help us out by revising, improving and updating this answer.
Update this answerAfter you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.