I've had a few people stop by my office and talk to me about exercises S3 and S4 from the supplementary exercises for Section 2.3 (part 1). Many of you are trying to mimic the example I did in class, which is a good thing to try. You can do this, but it is much harder. When I said, "Use the given graph", I was trying to get you to think about an easier way. On both problems, if you can figure out what the $x$-values labelled with question marks are, you are mostly done. Take $\delta$ to be the smaller of the two distances from the given $x$-value (which is 1 on the first problem and 2 on the second) to the question marks on either side. That's all you need to do. You don't have to solve any wild inequalities with absolute values.
Hints for Assignment 8 (Section 2.3, part 1)