The condition for lines to parallel is that they must have the same slope.
y = (2/3)x - 17, by comparing to y = mx + c, slope m = (2/3).
4x - 6y = -6
-6y = -4x - 6 multiply through by -1
6y = 4x + 6
y = (4/6)x + 6/6
y = (2/3)x + 1 comparing to y = mx + c, slope m = 2/3.
So the slopes for the two lines are equal, so the pair of lines are parallel.