Dividing things with coefficients and variables (called monomials or terms) is almost exactly the same thing as multiplying. First, we can rewrite each term the long way using the fact that exponents represent repeated multiplication. Then we use the fact that when a number or variable is divided by itself, they “cancel” each other out to be one.
In short, when you divide, you should divide the coefficients and subtract the exponents.
In contrast, when you multiply, you should multiply the coefficients and add the exponents.