perplexus.info :: Geometry : Parallelogram Requirement

Parallelogram Requirement (Posted on 2013-07-07)

Let ABCD be a convex quadrilateral.

Prove that ABCD is a parallelogram
if and only if
|AC|² + |BD|² = |AB|² + |BC|² + |CD|² + |DA|².

See The Solution Submitted by Bractals

Rating: 3.0000 (1 votes)

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	Subject	Author	Date
	Proof. No picture.	Jer	2013-07-09 11:00:04

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