A line parallel to the given one will have the same slope, 0.5. For the purpose here, it is convenient to start with a point-slope form of the equation, then simplify. For slope m and point (h, k), the equation of the line can be written as
... y = m(x -h) +k
We have m=0.5, (h, k) = (-9, 12), so the equation is ...
... y = 0.5(x +9) +12
... y = 0.5x +16.5
