How do I factor this:

6m^2 + 7mn + n^2

I really don't understand this one

well, 6 + 1 is 7 luckily

so try something of form
(6m+n)(m+n)

= 6m(m+n) + n(m+n)
= 6 m^2 + 6 mn + 1 mn + n^2
= 6 m^2 + 7 mn + n^2