As you may have noticed, some notations can be a little confusing until you have used them enough to get used to them. For example, (-3, 4) could be either an ordered pair or an interval; without context, you can’t know for sure. The first handout in the section has examples for all of the variations that you might see for interval notation, as well as an explanation of ordered pairs.

Confusing Notations – Ordered Pairs and Interval Notation