The American house-carpenter; a treatise on the art of building, and the strength of materials (1867)
Hatfield, R. G. (Robert Griffith), 1815-1879 · New York, J. Wiley · leaf 78
a triangle amount toa right angle, the remaining angle is a right angle. 153.—Corollary. If any two angles of a triangle are togetherequal to the remaining angle, that remaining angle is a rightangle. 154.—Corollary. If any two angles of a triangle are eachequal to two-thirds of a right angle, the… … Fig. 107. 156.—Proposition. If from the extremities of the diameter ofa semi-circle, two straight lines be drawn to any point in the cir-cumference, the angle formed by them at that point wiVi be aright angle. Let ah c, {Fig. 107,) be a given semi-circle , anda b and h c, lines drawn from the…
Carpentry · Architecture
Internet Archive · Library of Congress · Public Domain Mark 1.0. Free to use for anything.
![An illustration from Divina proportione : opera a tutti glingegni perspicaci e curiosi necessaria oue ciascun studioso di philosophia: prospettiua pictura sculptura: architectura: musica: e altre mathematice: suavissima: sotile: e admirabile doctrina consequira: e delecterassi: co[n] varie questione de secretissima scientia (1509)](https://img.insideoutlibrary.com/img/200/ia-divinaproportion00paci-31-34.webp)
