Pythagorean conics and homothetic triangles

Antonio Alfonso Arcos Álvarez; Emilio González Abril; María-Jesús Vázquez-Gallo

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arXiv · 2511.00007

Pythagorean conics and homothetic triangles

Antonio Alfonso Arcos Álvarez·Emilio González Abril·María-Jesús Vázquez-Gallo

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Abstract

This study investigates a generalisation of the Pythagorean theorem to the lengths of conic arcs constructed symmetrically on the sides of a right triangle. It is demonstrated that the theorem remains valid whenever the conic eccentricity is fixed and the ratio between the length of each arc sagitta and its corresponding side is constant. We identify the existence of a Pythagorean centre, defined as the common centre of all homotheties between the original right triangle and the enveloping right triangles of the infinite set of Pythagorean triples of conics that can be derived from it. The proofs rely on the application of both geometrical and analytical techniques starting from classical Pythagoras theorem.

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BibTeX RIS

Antonio Alfonso Arcos Álvarez, Emilio González Abril, María-Jesús Vázquez-Gallo. 2025-10-11. Pythagorean conics and homothetic triangles. https://arxiv.org/abs/2511.00007

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