6. If (1, 2), (4, y), (x, 6) and (3, 5) are the vertices of a parallelogram taken in order, find x and y.
Let the given points .
Since the diagonals of a parallelogram bisect each other. Intersection point O of diagonal AC and BD also divides these diagonals.
Therefore, O is the mid-point of AC and BD.
The coordinates of the point O when it is mid-point of AC.
The coordinates of the point O when it is mid-point of BD.
Since both coordinates are of same point O.
Therefore,
and
Or,