Answer
$81$; John multiplied the bases.
Work Step by Step
John multiplied the bases. The base should remain the same after the exponents are added.
$9^{-58}(9^{60})$
$9^2$
$81$
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.