Proposition. The midpoints M, N, and P of the
diagonals AC, BD, and EF of a complete quadrilateral ABCDEF lie
on a line called NewtonGauss Line.
Click the
red button ()
on the figure to start the animation.
Drag points A, B, C, D, and F to change
the figure. Try the step by step
construction.
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.
Midpoint of a segment: the point on a line segment
dividing it into two segments of equal length.
Dynamic Geometry: You can alter the figure
dynamically in order to test and prove (or disproved)
conjectures and gain mathematical insight that is less
readily available with static drawings by hand.
This page uses the
TracenPoche
dynamic geometry software and requires
Adobe Flash player 7 or higher.
TracenPoche is a project of Sesamath, an association of French
teachers of mathematics.
Instruction to explore the
dynamic figure:

Animation. Click the red
button
to start/stop animation

Manipulate. Drag points A
and C, and line AC to change the figure.

StepbyStep construction.
Press P and click the left mouse
button
on any free area to show the
stepbystep bar and click 'Next
Step' button ()
to start the construction stepbystep:
Hide the stepbystep bar by
using again the combination P +
click left mouse.
