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arXiv · 2207.06230

Intersections of vertical lines with non-vertical lines

Mateusz Kula
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Abstract

We answer negatively a question: if $\mathcal F$ is a family of $n\geqslant 3$ non-vertical, pairwise non-parallel lines on the plane and $\bigcap \mathcal F=\emptyset$, is there a vertical line $L$ such that $L\cap\bigcup \mathcal F$ has exactly $n-1$ or $n-2$ points?

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Mateusz Kula. 2022-07-12. Intersections of vertical lines with non-vertical lines. https://arxiv.org/abs/2207.06230

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