# Factorise using Common Factors

## Transcript

Guys in these questions you have to ask yourself what is common? Or what is the common factor? Okay? Factor is the keyword here when you’re factorizing that’s why it’s factorizing okay? So in 2a and ab what is the common factor?

What is common? So what’s commonly ask yourself what’s common.
See how they both have a? So a is common so what I’m going to do is take an out of the bracket and inside the bracket he will just have two left and he will just have b left because I took an out in each of them okay? Get the idea?

That’s what we’re doing with factorizing, so when you go to expand it out, so you do the same thing as we did in the previous part, times two and a times b. You should have this, okay so you can check if you do have the time you can double-check by expanding it. All right? So anything common just takes it out at the front so that’s uh 18 19. We’ve got a squared minus two ab, so ask yourself again what is the common factor?

Now what I’m going to do here guys change a squared to aa because a times a is a squared, isn’t it? So I’ve just kind of expanded that out, so a squared is aa, and that one just leave it as is now guys. What is common?

a is common, isn’t it? a is the common factor but only one a so here you see how we have one a so we also take one a out of here as well. So let’s take the a out like that so here I’ve took one of the a’s out so we just have one a left inside and here I took a out, so we just have minus two b left okay? So make sure although a is common.

Don’t take the whole thing out. You only take one of them out because that one has only one a. Okay? get the idea?