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--- Introduction ---
A homothety of the plane is a zoom (magnification or reduction) of
the plane. The center of a homothety is the unique point of the
plane which stays unchanged after the homothety.
Homothety shoot is a visual game/exercise.
It presents you two shapes, one being the image of the
other after a homothety in the plane. And you are asked to find out the
center of the homothety by clicking on the picture.