Answer
$-1$
Work Step by Step
$\dfrac{x-7}{7-x}$
Rewrite the denominator by changing its sign. To do so, also change the sign of the fraction. After that, simplify:
$\dfrac{x-7}{7-x}=-\dfrac{x-7}{x-7}=-1$
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.