To multiply or divide terms, you do not have to have like terms.

This is different from addition and subtraction, so be careful! Take a look at the following example of basic multiplication with a variable:

We must multiply every part of the equation inside parentheses by 2, and this example shows that happening in the second step, where it's gone from (x + 5) * 2 to (2 * x) + (2 * 5). After we multiply, our final answer is a simple 2x + 10.

Now that we can do the basics, let's make it a little harder and include another variable:

Despite having two variables this time, our procedure is the same as it was in the first example, in which (x + 3) * y turns into (y * x) + (y * 3). In other words, we have to multiply everything inside the parentheses by our variable y, which leaves us with an answer of xy + 3y. We can't combine our xy with y, so this is the simplified expression.