So basically you want to find x.
To find x in this, move the -3 to the other side by adding 3 on both sides:
1/2x – 3 + 3 = -9 + 3
1/2x + 0 = -6
1/2x = -6
Now, all you have to do is to ask yourself: How many halves does it take to get -6? It’s simple: multiply both sides by 2, because then 1/2 × 2 is 1, so 1/2x × 2 is x, so -6 × 2 is -12.
1/2x × 2 = -6 × 2
x = -12
So, your answer is x = -12