American text books of art education : Geometrical drawing (1873)
Smith, Walter, 1836-1886 · Boston : James R. Osgood & Co. · leaf 70
Prob. 71. — To construct an isosceles triangle on a given base A Bhaving a vertical angle of 90°. Draw A B. The two angles at the base of an isosceles triangleare equal; and as the vertical angle is to be 90°, each angle at thebase will be half of 90°, or 45°. At point A make a right angle;bisect…
Geometrical drawing
Internet Archive · Boston Public Library · Public Domain Mark 1.0. Free to use for anything.
