Lines A and B are parallel. Lines A and B apre perpendicular to Line C.
Change all of the lines from standard form to slope-intercept.
Line A: y = 4/3x + 2/3
Line B: y = 4/3x + 2
Line C: y = -3/4x + 1
Since A and B have the same slope they are parallel. C has a negative reciprocal so it's perpendicular.