Combine like terms (those with the same amount of variables:
x + x + x + x = 4x
4x - 20 => Note: You cannot combine these two terms, because they do not have the same amount of variables (one having one variable (x), the other being a constant (no variable) ).
I'm not good with intigers, but if you added two negative intigers together wouldn't it still be negative? If you added -1 to -2 you'd get -3. It would always be less than the two original integers.
