The elements of Euclid : viz, the first six books, together with the eleventh and twelfth : the errors, by which Theon, or others, have long ago vitiated these books, are corrected, and some of Euclid's demonstrations are restored : also, The book of Euclid's data, in like manner corrected (1834)
Euclid, Euclid, Simson, Robert, 1687-1768 · Philadelphia : Desilver & Thomas · leaf 203
B PROP. XXXIX. THEOR. In a solid parallelepiped, if the sides of two of theopposite planes be divided each into two equal parts,the common section of the planes passing through thepoints of division, and the diameter of the solid paral-lelopiped cut each other into two equal parts.* See Note, 200… … E Let the sides of the Dopposite planes CF,AH of the solid paral-lelopiped AF, be di-vided each into twoequal parts in thepoints K, L, M,N5 X,O, P, R; and join KL,MN, XO, PR: andbecause DK, CL areequal and parallel, KLis parallel (33. 1.) toDC: for the same rea- Bson, MN is parallel toBA: and BA is…
Mathematics, Greek · Geometry · Trigonometry
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