Selected propositions in geometrical constructions and applications of algebra to geometry. Being a key to the appendix of Davies' Legendre (1875)
Legendre, A. M. (Adrien Marie), 1752-1833, Davies, Charles, 1798-1876 · New York, Chicago [etc.] A.S. Barnes & company · leaf 41
34 KEY. Hence, from Bk. IV, Prop. 16, PQ is parallel to DB. In like mannerit may be shown that RS is parallel to DB: hence, PQ and SR areparallel to each other. The lines QR and PS are parallel to AC, forsimilar reasons; hence, they are parallel to each other, and conse-quently, the figure PQRS is… … Q M Prop. XLVIII.—Inscribe in a given triangle, a triangle whose sidesshall be parallel to the sides of a second given triangle. Solution.—Let ABC be the first given triangle, and let DEF bethe second given triangle. Take any point P, on the side AB, andthrough it draw PQ parallel to DE; fromQ draw…
Geometry
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
