Non-Euclidean Geometries - Cornell University

2.4 Distance, Ruler Postulate, Segments, Rays, and Angles. Being able to measure distance is not a property that comes automatically with a geometry. We did not have distance in any of the non-Euclidean geometries we’ve studied so far. With these axioms we can begin measuring the distance between 2 points and the length of a segment. ................
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