The first six books of the elements of Euclid, in which coloured diagrams and symbols are used instead of letters for the greater ease of learners (1847)
Byrne, Oliver, Whittingham, Charles, 1795-1876, Chiswick Press · London : William Pickering · leaf 69
\ (pr- 26.) and ^^W = ^^M (^^^Therefore the oppofite fides and angles of the parallelo-gram are equal: and as the triangles .N.^ are equal in every refpect (pr. 4,), the diagonal divides the parallelogram into two equal parts. Q. E. D. 36 BOOK I. PROP. XXXV. THEOR.
Euclid's Elements · Geometry
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