Final answer:
The lines a and b are neither parallel nor perpendicular.
Step-by-step explanation:
The lines a and b can be determined by finding their slopes. The slope of a line is given by the formula m = (y2 - y1) / (x2 - x1). Let's calculate the slopes:
Line a: m = (0 - 4) / (6 - 0) = -4/6 = -2/3.
Line b: m = (2 - (-1)) / (6 - 4) = 3/2.
Since the slopes of the lines are not equal and their product is not -1, the lines a and b are neither parallel nor perpendicular. They are just two non-parallel lines that intersect at some point.