5>2 D E R E S O L V T 1 O N E 



A-4-B+E = ^BD-|-i8o°-BADm8o°-|-BDA, 



quod omnino rede fe haber, cft cnim 



fin. B D A : fiii. B A D : : B A : B D , tumque 

 fm. D C ^ : fin. D B C : : B D : C D , 



quare componeiido rationes 



fin B D A — B A./ tri.B \ D./ /1. PBC 



CD.jm.DCc * 



feu introduftis exprtliionibus analyticis 

 fin. B D A - 'Juii^^JL^, 



cjin.C 



$i ponatiir A -h B + E :z= 180'' -j- F , facile p.Ue'^ 

 arcum 3<)D°— F eunJcm habcre fiiium ac 180 +F , 

 ficquc pro B duphccm prodire valorem , quorum 

 prior c(t Br:i8o"H-F-A-H,alrcrB'-36o"-(A-hh-fF). 

 Idcm vero ex contempl.iiione figurae inanikftum rcd- 

 ditur , dcfciipto etenim tiinngulo B C D pro quo 

 dantur bina latcra BC, CD cum angulo BCJ), 

 habebitur pu;(fluin A quadnlatcri dcfcribcndo lupcr 

 dia9;onali B D (egmcntum circul , cniod fufcipit an- 

 gulum — 180° — A , ct centro B r.idio zz a ciicu- 

 lum' , pro A enim affbmi potcrit altcrutrum puii- 

 <flum interfeiflionis huius circuli cum illo (cg-iiento, 

 \nde (ponte conficitur pro angulo B binos emer.;erc 

 valorcs. Sint binae hae Mtericcflioncs A , a' et du- 

 cantur lineac Z?BA , ^'BA', fi igitur anguhis 3BC 

 pro noftra figura defignetur pcr B, crit Z)'BC = B', 

 qiiare oportct e(fe Z>' BC — Z^BC— 1 80°— 2F. Ell 

 "vcro F~BDA , quare ficri oportec : 



^^'BC-Z-BCn ABA'= iSo^-^BD A , 



quod 



