CabriJava demonstration of Desargues Theorem

Desargues Theorem states that, if AA', BB', and CC' are concurrent (at D), then
The intersections (P, Q and R) of AB with A'B', CA with C'A' and BC with B'C' are collinear.

You may move any of the points A,B,C,A',B',C' or D
by clicking on them and dragging them to a new position
You will see that P, Q and R remain collinear.

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