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| | AXIOMS |
 | | Any one of these axioms together with the axioms of Neutral geometry (incidence axioms I-1, I-2, I-3; betweenness axioms B-1, B-2, B-3, B-4; congruence axioms C-1, C-2, C-3, C-4, C-5, C-6; and Dedekind's continuity axiom) give a complete system of axioms for the Euclidean geometry. |
 | | Perspectivities preserve separation; i.e., if (A, BC, D), with l the line through A, B, C, and D, and P, Q, R, and S are the corresponding points on line m under a perspectivity, then (P, QR, S). |
 | | * in elliptic geometry the betweenness axioms are replaced with separation axioms. |
| www.southernct.edu /~pinciuv/m360axio.html (960 words) |
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