on test day!
1) for this one, we need to figure out all the possibilities first, then find them among the answer. point a is at x = –1. if point b is two units away from point a, it could be to the right or to the left: in other words, point b could be at x = +1 or x = –3. we have to keep both of those point b possibilities in mind when we consider the possible locations of point c. point c is 3 units away from either point b, either to the right or to the left.
those four are the possible locations of point c. 