Answer
19
Work Step by Step
According to the general properties of common logarithms on page 462, $b^{log_{b}x}=x$.
Therefore, $8^{log_{8}19}=19$.
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.