Work Step by Step
$d(a,b)=|a-b|=|b-a|$ (page 7) Now make $a=x$ and $b=25$. No more than 10 means $\leq10$ $|x-25|=|25-x|\leq10$
You can help us out by revising, improving and updating this answer.Update this answer
After 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.