The midpoints N, W, and T of the diagonals AC, BD, and EF of a complete quadrilateral ABCDEF lie on a line called Newton-Gauss Line.
Complete quadrilateral ABCDEF is the figure determined by four lines, no three of which are concurrent, and their six points of intersection A, B, C, D, E, and F.
	     
 

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			Complete Quadrilateral
 
			
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