(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

I have to show that the Poincare disk satisfies the incidence axiom that any line contains at least two points.

2. Relevant equations

There are two kinds of lines on the Poincare disk. I've found 2 points for the first kind, which are straight lines going through the origin. The second kind are lines

L a,b = {(x,y) | (x-a)^{2}+ (y-b)^{2}= a^{2}+ b^{2}- 1, with x^{2}+ y^{2}< 1}

3. The attempt at a solution

Given a and b, I need to find (x, y) and (x',y') that lie on the line.

I've shown that x^2+y^2+1 = 2ax+2by, but I don't know if I'm headed in the right direction.

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# Homework Help: Show Poincare Disk is incidence geometry

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