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Geometry/Neutral Geometry/Pasch and Crossbar
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Pasch's Theorem
If A, B, C are distinct noncollinear points and l is any line intersecting AB in a point between A and B, then l also intersectseither AC or BC. If C does not lie on l, then l does not intersect both AC and BC
Explanation
Crossbar Theorem
If ray AD (need LaTex formatting) is between ray AC(need LaTex formatting) and ray AB(need LaTex formatting), then ray AD(need LaTex formatting) intersects segment BC
Explanation