The idea is to get Y by itself, which will convert the equation from Standard Form to Slope Intercept Form. The following is a step-by-step answer to your question:
1. Since you want Y on the left side, just change the equation to 2y+12=2x.
2. Subtract 12 from left side and right side. 2y=2x-12.
3. Get 2y to y by dividing each side by 1/2. y=x-6.
4. This is your final answer in y=mx+b format. y=x-6.
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