Given 3 + 4x - 3x = 4
Next is Combine like terms, so you combined the one that has a variable which is 4x-3x = 1x or just an x.
Combine like terms 3 + x = 4
Next is subtraction property of equality, so you will subtract 3 in both side like this...
3-3 + x = 4-3.
Subtraction Property of Equality 3-3 + x = 4-3
then the answer will x = 1 .