Category:Complete Quadrangles

This category contains results about Complete Quadrangles.
Definitions specific to this category can be found in Definitions/Complete Quadrangles.

A complete quadrangle is a quadrangle whose $4$ points are joined by $6$ lines: one connecting each pair of points.

It is complete because every pair is connected.

Diagonal Points

Let $A$, $B$, $C$ and $D$ be the points of a complete quadrangle $ABCD$.

The diagonal points of $ABCD$ are the points of intersection of the lines:

$AB$ and $CD$

$AC$ and $BD$

$AD$ and $BC$.

In the above diagram, $ABCD$ are the initial $4$ points being connected.

The three diagonal points are $R$, $S$ and $T$.