Elements of geometry : containing the first six books of Euclid, with a supplement on the quadrature of the circle, and the geometry of solids : to which are added, Elements of plane and spherical geometry (1826)
Playfair, John, 1748-1819, Euclid · Philadelphia : Marot & Walter · leaf 284
On AB let a triangle he eonstituted every way eqn alto the triangleDBF; then if this triangle coincide with the triangle ABC, it is evi-dent that the proposition is true, for it is equal to DBF by hypothesis,and to ABC, because it coincides with it; Wherefore ABC, DEF areequal to one another. But…
Euclid's Elements · Geometry · Trigonometry
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