Question 39689
You need to get the variables to one side first
19-3n =  2n
  +3n   +3n
______________
19   =  5n

then divide by 5 on both sides to get rid of the 5

19   =   5n
---      ---
5         5

3 4/5 =   n

subsitue 3 4/5 for N and check your answer