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atjari
Please help. Prove that the diagonal of a quadrilateral bisect each other if and only if it is a parallelogram.
I didn't read the problem properly, now after I did, I think we can prove this easily using vectors.
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Ya v need to solve t with vectors nly. Bt hw?
Note the congruence of the triangles,and you can proceed easily.
This is a pure geometrical solution http://www.math.washington.edu/~king/coursedir/m444a00/test/ca10-16-pgramdiag.html
geometrically I can prove t. Bt this question comes under the section vectors. That's y am confused.
I am sooo tired right now :(
Ha k. Anyway thanx for trying to help me.