A generalization of the Nepoleon Theorem

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A construction of cardioid, using dilation

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...and a similar construction of the nephroid

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Vecten's Figure (1817) Reference: Yvonne Sortais, Geometrie de l'espace et du plan: synthese de cours, exercises resolus, Paris, Hermann, 1988, p. 114

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Parabola tangent to a complete quadrilateral
JavaSketchpad File

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