The first six books of the elements of Euclid : with a commentary and geometrical exercises ; to which are annexed a treatise on solid geometry, and short essays on ancient geometrical analysis, and the theory of transversals (1861)
Lardner, Dionysius, 1793-1859 · London : Print. for Taylor and Walton · leaf 256
e B E and C F are equal and parallel, andhence B C and EF are equal and parallel. Thetriangles BAC and EDF are therefore mutually equilateral,and therefore mutually equiangular, and hence the angle BACis equal to the angle EDF. The planes BAC and EDF are parallel, for if not drawthrough A a plane… … 238 ELEMENTS OF SOLID GEOMETRY. Proposition XXII. (45) If the planes of two equal angles (B A C and E D F) and one pair of their legs (A B andD E) be parallel, and the other pair of legs(A C and D F) be at the same side of theparallel legs, they will also be parallel. For if AC be not parallel to…
Geometry
Internet Archive · Public Domain Mark 1.0. Free to use for anything.
