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# Title: An Introduction To Algebra (shelfmark Leibn. Marg. 87)
# Folio 93, page id 827130880:0109
# Original at the GWLB: https://digitale-sammlungen.gwlb.de/resolve?id=827130880&page=109
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d
 2
1
-
 dd
Resolution of Problemes.
A Proposrion
Ein an oblique crianole, a perpendicular be let FaIL FTOMM ANV
thenis che
Dupon the oppolite lide ichin or michout the trianele;
iHference oFche squares oF the sides (AB, and BC)
conteimins che Caid angle equal to the difference oF thie lines
AD and CD) conteined betreen the perpendicular and BOFh
d
encs oEille ue (et oppohce lice atorelata.)
b
2.
1 AB =-aa 1 2ab 1 bb
AC + CD = d 1 0 = AV
SH AD. =dd 1 2de t ee
E BC =CC
(OAC D = eC
C+ D AB EsBC = a A t 2 ab + bb - cc
c2 1 AD DCD =- dd- 1 2de
23) aa 1 2 ab t bb - c0 = dd F 2de a5 Cay es ch PropOlicion
14
15
Demonstration.
aa 1 2ab + bb, dd- ec- 2de = BBD
C6 e6
=HBD
16 aa l 2 ab + bb dd - 2de - c0 =0
17 aa- + 2ab t bb - c0 = dd 1 2de 25 above in (+3) 9. C. d.
And alter ehis ray may all sorts oF Geometricat PropOLi
tions Dedemonstrated.