Davies, Charles, 1798-1876 · New York and Chicago, A. S. Barnes and company · leaf 101
quently it is similar toDEF THEOREM XVIII. ij from tlie right angle of a right angled triangle, a perpen-dicular be let fall on the hypothcnuse, then I. The two partial triangles thus formed will be similar toeach other and to the whole triangle. lx. Either side including the right angle will be a… … Let ABC be a right angledtriangle, and AD perpendicularto the hypothenuse. The two triangles BAC andBAD having the common angle5,and the right angle BAC equalto the right angle at D, will be equiangular (lik. I. Th. xviiCor. 1); and, consequently, similar (Th. xv). For a likereason the triangles…
Geometry · Plane trigonometry
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-84-118.webp)
