Look at these examples:
Addition and subtraction
We use más (plus) and menos (minus), and then igual a (equals).
However we also have other, simpler ways to express it:
using y (plus, and) and son (equals).
We sometimes omit the "equals" part and just use a comma.
Have a look and listen to these examples:
We use por (times) or multiplicado por (multiplied by). We can also omit the equals part and use a comma or "son".
We use dividido entre (divided by) or the simpler version: "entre". We can also omit the equals part and use a comma or "son".