Question

If the points A (a, -11), B (5, b), C (2, 15) and D (1, 1) are the vertices of a parallelogram ABCD, find the values of a and b.

Answer 1

Let A(a, -11), B(5, b), C(2, 15) and D(1,1) be the given points.

We know that diagonals of parallelogram bisect each other.

Therefore, Coordinates of mid-point of AC = Coordinates of mid-point of BD