First things first, separate the terms, 4m -m + 2n - n Change it to 3m (as you remove one) + n (because one is removed). So the end result would be 3m +n.
First you need to find the like terms, which would be the terms multiplied by the same letter, so: 4m, -m 2n, -n Now if you add them together, you get 4 - 1 = 3m, and 2 - 1 = n, so your final answer is 3m + n
