If you simplify what's in the bracket, you get 3n
=(3n)+4=32/2
=3n+4= 32/2(here we can either crossmultiply or equate)
3n+4-4=32/2-4(subtract 4 from both sides)
3n=32/2-4
3n=24/2
3n=12
3n=12(divide both sides by the coefficient of the unknown)
3n/3=12/3
n=4