If the points (-2 , -1), (1, 0), (x, 3) and (1, y) form a parallelogram, find the values of x and y.
Let given points be A(-2, -1), B(1, 0), C(x, 3), D(1, y) and let the intersection of diagonals be E(xm , ym )
It is given that □ABCD is a parallelogram.
By midpoint formula.
x = , y =
We know that midpoint of parallelogram coincide.
∴ Midpoint of AC = Midpoint of BD
∴ ( ,
) = (
,
)
∴ =
and
=
∴x = 4 and y = 2