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Geometry Difficulty 4.7 AIME Prove it Greece

Is it possible to put on the plane 20142014 points, so that with vertices from these points to construct 100621006^2 parallelograms of area 11?

Solution

We shall prove that it is possible. We consider two parallel lines ε1,ε2\varepsilon_1, \varepsilon_2 with distance 11. We put on each of them 10071007 points such that every two successive of them have distance 11. Then we have in the line ε1\varepsilon_1 10061006 segments of length 11 and in the line ε2\varepsilon_2 we have also 10061006 unit segments. Any pair of unit segments having members from both lines gives rise to a parallelogram of area 11. Therefore we have totally 100621006^2 parallelograms of area 11.

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