Q5 of 77 Page 7


Show that the points A(1, 0), B(5, 3), C(2, 7) and D(-2, 4) are thevertices of a parallelogram. (Hint: Diagonals of a parallelogram bisecteach other).

PROOF:

We know that the midpoint of a line segment AB with A(x, y) and B(u, v) is
The midpoint of diagonal AC is Â
The midpoint of diagonal BD is
So, the diagonals AC and BD bisect each other

⇒ ABCD is a parallelogram.
Hence, proved.

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