Question

The three vertices of a parallelogram taken in order are (-1, 0), (3, 1) and (2, 2) respectively. Find the coordinates of the fourth vertex.

Answer 1

Let A(-1,0) B (3,1), C(2,2) and D (x, y) be the vertices of a parallelogram ABCD taken in order.

Since, the diagonals of a parallelogram bisect each other.

So, coordinates of the mid point of AC = Coordinates of mid point of BD

The fourth vertex of parallelogram = (-2,1).