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 75
C E … gle at G is equal to the angle at H; therefore the base BC isequal (4. 1.) to the base EF; and because the angle at A is equalto the angle at D, the segment BAC is similar (l 1 def. 3.) to thesegment EDF; and they are upon equal straight lines BC, EF;but similar segments of circles upon equal…
Mathematics, Greek · Geometry · Trigonometry
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