If the line is parallel, then their slope would be equal.
4y = -x + 6
y = -1/4 x + 3/2
Compare it with, y = mx + b
m = -1/4 [ Slope ]
Now, y - y1 = m(x - x1)
y - 5 = -1/4 (x + 8)
y - 5 = -1/4x - 2
y = -1/4x + 3
In short, Your Answer would be: y = -1/4x + 3
Hope this helps!