I'm reading Pogorelov's *Geometry*.

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> Find the line segments cut off by the plane $ax+by+cz+d=0$ on the coordinate axes, if $abcd\neq 0$.
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Writing the equation as $a(x-x\_0)+b(y-y\_0)+c(z-z\_0)=0$, I think that the line segment is $(x-x\_0)$. But when the equation is written as $ax+by+cz+d=0$, I have no clue as to how to think about it.