Question

X+2x-3+x+4 = solve for x

Answer 1

This is not an equation and thus cannot be solved for x.  Ensure that you have copied down the original problem exactly.

If, on the other hand, you meant    x + 2x - 3 + x = - 4, you do have an equation and can solve for x as follows:

4x - 3 = -4        =>                4x = -1        =>           x = -1/4