You can put this solution on YOUR website! Remove the common factor found in each term.
Then divide each term by that common factor.
The common factor found in each term is 3.
Do you see 3 in each term?
3m^2 divide by 3 = m^2
3n^2 divide by 3 = n^2
We now have this: 3(m^2 - n^2)
Inside the parentheses, we have what is called the difference of two perfect squares. We can factor that out to be (m - n)(m + n).
Final answer: 3(m - n)(m + n)
NOTICE: The final answer has 3 factors. Do you see the factors?