qttibus valoribus fubftitutis prodibit 



, , -»,v, i <2 a a — b b — e e 



$ — x ^-y + z=3x + 



tmde porro colligitur: 



~. I _r_ b b -h c c — 2 a a 



X — - 3 S-r-. - , 



z =r Is-r- 



a a -+- b b — 2 c c 



3 3s 



Pro determinanda incognita s vocetur area trianguli dati 

 A 5 eritque haec area 



A zzr | iin. 6o° (xy + xz+/z). 



Cclligantur iani in unam furamara ternae aequationes pri- 

 mariae, atque habebimus 



a» + {)b+-cczz 2(xx+j/ + zz) + x/ + xz+)"2;. 

 Eft vero 



xj + xz+jJS-^z:^ 

 confequenter 



aa-r~bb-hccz=z2 (xx+jj + zz) "+" ti> 

 unde colligitur: 



XX+JJ + Z^= «a+bb^cc __2A_ 



Huic aequationi addatur feqtiens: 

 2 (x y -\- x z -}- y z) = ^A, 

 atque prodibit 



(X+J + 2) 2 = ^Z: ««-4-^-J-cc ^_ ^ 



ita tit fit 



s =3 /(" + y + (t +2A/3). 



Prc- 



