That's unusual: repetition: -1/2 - 1/2.
Did you perhaps mean "Factor -1/2 out of (-1/2)x + 6?
Let's do that. Let's rewrite 6 as (-1/2)(-12).
Then (-1/2)x + 6 (-1/2)x -(1/2)(-12)
-------------- = ------------------------ = x - 1/2
-1/2 -1/2
Hope that's what you wanted. If not, please try to apply a similar approach to solving this particular problem.