document.write( "Question 1006481: Prove that in a parallelogram the sum of the squares of the diagonals equals the sum of the squares of the four sides \n" ); document.write( "
Algebra.Com's Answer #622610 by ikleyn(52781)\"\" \"About 
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\n" ); document.write( "See the lesson  The length of diagonals of a parallelogram  in this site.\r
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