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arXiv · 2105.00919

Lattice equable quadrilaterals II -- kites, trapezoids and cyclic quadrilaterals

Christian Aebi·Grant Cairns
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Abstract

We show that there are 4 infinite families of lattice equable kites, given by corresponding Pell or Pell-like equations, but up to Euclidean motions, there are exactly 5 lattice equable trapezoids (2 isosceles, 2 right, 1 singular) and 4 lattice equable cyclic quadrilaterals. We also show that, with one exception, the interior diagonals of lattice equable quadrilaterals are irrational.

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Christian Aebi, Grant Cairns. 2021-04-30. Lattice equable quadrilaterals II -- kites, trapezoids and cyclic quadrilaterals. https://arxiv.org/abs/2105.00919

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