Hi. One topic I cover in week one of a college algebra course is division by zero. We are going to see this later on in the chapter on rational functions, so I think we ought to settle this issue sooner rather than later. Most people reading this blog are well-aware that division by zero is an undefined operation in the rules of real and complex number arithmetic. 3/0 = undefined.
This is often quite a surprise to my students, who apparently never learned this anywhere in their K-12 educations. Truthfully, I can't remember learning it in my K-12 education either. I think my fourth grade teacher is on Facebook, and I'm going to ask her if she remembers teaching it.
I invite my students to try 3/0 on as many calculators as they own. Sometimes the calculator will show "Error" (which is descriptive, but is not a correct answer), and sometimes it will show zero (which is worse). Students are even more surprised when I tell them both of these calculator results are incorrect. However, we also experiment on calculators with Order of Operations problems, so students discover that not every calculator follows those rules.