For a line to be parallel, the slope has to be the same(1/3) only its coordonate on the y axis (b) changes.
Therefore the new equation will be y=1/3x+b
To find be, tou have to isolate it after inputting the new coordinates (-9,4)
(4)=1/3(-9)+b
4=-3+b
7=b
Therefore, the new equation is
y=1/3x+7