Inside Out Library
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 180
©F GEOMETRY. BOOK II. 179 in the plane d aw any strais^ht linr BC, an from the point A draw(l2. 1.) AD perppnrlicular to BC. If then AD he also perpt-ndieu-lar to the plane BH, the thin^ required is alreadv Hone; but if itbe not, from lb* point D draw ^ /[\(11. 1.), in the plane BH, thestraight… … AF perptniiicular to DE; andtbroujrh Fdraw (31. 1.) GH pa-rallel to BC: and because BC isat ria;ht angles to ED, and DA,BC is at right angles (4. 2. Sun.)to the plane passing through ED, DA. And GH is parallel to BC ; but if two straight lines he parallel,one of which is at right angles to a plane,… Euclid's Elements · Geometry · Trigonometry
Internet Archive · Public Domain Mark 1.0. Free to use for anything.
More pictures from 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
More like this 
