The diagonals of a rectangle P, Q,R,S intersect at (5,3). Given that the equation of line PQ is 4y-9x=13 and that of line PS is y-4x=5. Find. a) The co-ordinate of p b) The co-ordinate of R c)The equation of line RQ d) The equation of a perpendicular line drawn to meet PR at (5,3)