Question 1094458
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The wording form of this statement is this Theorem:


<pre>
    If in a quadrilateral two diagonals bisect each other,  then the quadrilateral is a parallelogram. 
</pre>

It was proved in the lesson

&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=http://www.algebra.com/algebra/homework/Parallelograms/Properties-of-diagonals-of-parallelograms.lesson>Properties of diagonals of parallelograms</A> 

in this site (Theorem 2).