Answer :

most people use the decomposition method but i dont know how to do that so i use the Joes method a method similar to decomp. but easier.
canadian way

Find gcf: None
complet trinomial: 18n^2+57-10
find the product=10(18)
                       =-180
find the sum     =57
-3 and 60 goes into both meaning if you multiply 3 and60 you get -180 and if you add them you get 57.

so (n-3)(n+60)
divide by a in this case it 18
so (n-3)(n+60)
       18     18
do not divide. treat it like a fraction so you reduce it to lowest terms
(n-3)(n-3)
  18   10
at this point its reduced to lowest terms so now you take the deniminator and move it beside the "n"

=(18n-3)(10n-3)

therefore your answer is (18n-3)(10n-3)
I hoped this helped :)