factor 3a^2(a-b)-6a(a-b)+21(a-b)

Question

Can you show me the steps? I'm just not getting it :(

You can take a 3 out of everything.

3[(a^2)(a-b)-2a(a-b)+7(a-b)]

You can also take out (a-b)

3(a-b)[(a^2)-2a+7]

I'm pretty sure this is your answer.

Thank You. This was a big help :)

No problem! Glad I could help