y=12+3x

The standard form of a linear equation is Ax+By=C.

Rewrite the equation with the sides flipped.

12+3x=y

Subtract y from both sides of the equation.

12+3x-y=0

Move 12.

3x-y+12=0

3x-y+12=0

Subtract 12 from both sides of the equation.

3x-y=-12

Rewrite in Standard Form y=12+3x