The first six books of the Elements of Euclid, in which coloured diagrams and symbols are used instead of letters .. (1847)
Euclid, Byrne, Oliver · London, W. Pickering · leaf 65
oppofite angles ( and ^ Rt,), and the three internal angles ofevery triangle taken together areequal to two right angles. … Through the point / draw II (pr- 3 0- Then < ^^^ ( (pr. 29.),
Geometry
Internet Archive · Thomas Fisher Rare Book Library · Public Domain Mark 1.0. Free to use for anything.
