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 320
C D To … Proposition. 12) To draw a line from the vertex of a given triangle to the base, sothat it will be a mean proportional between the segments. Let A B C be the triangle, and let B D be a mean proportionalbetween A D and D C. Produce B D to E, sothat D E shall be equal to B D, and join C E. Since…
Geometry
Internet Archive · Public Domain Mark 1.0. Free to use for anything.
