Question 1009713
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If in a quadrilateral the two diagonals bisect each other,  then the quadrilateral is a parallelogram.


This is <U>Theorem 2</U> from the lesson <A HREF=http://www.algebra.com/algebra/homework/Parallelograms/Properties-of-diagonals-of-parallelograms.lesson>Properties of diagonals of parallelograms</A> in this site.