Question

Which monomials are factors of -21a^2?

Answer 1

There are many pairs you could do, but I'm going to choose this one:
$(-3a)(9a)$

You can multiply them together, and get (that's how you know if they are factors):
$(-3a)(9a) = -21a^2$

Hope this helped!

Answer 2

Answer:

the answer is 3a^2

Step-by-step explanation: