the anwser to this question is -2
The minus changes the signum of the values in the bracket, so:
4x + 7 - (x + 1) = 4x + 7 - x - 1 = 3x + 6
If you want the x:
3x + 6 = 0
3x = -6
x = -6/3 = -2
6.2m questions
8.2m answers