QJJADRATIC EQTJATIONS. 3^! 



^. Given jat"— i^^* — c:=i — d % to find ^. 



n 



First, ^A?"— ^x * nrc— ^ by transposition, 



b !L c—d 

 And A?"— — a;*zz:— — by division .; 



hi. 5» c— ^ ^» , . , 



Also a;" a:* -f "i = + 2 by completing the 



square. 



And ;c* — ~ =: s/ 1- — r by evolution 5 



2<l ^ 4^ 



Therefore J^=:- + ^Z— + -V, 



And consequently Pfir: — "^v '• 4- . — \ 



EXAMPLES FOR PRACTICE. 



1. Given x* — 8,Y-|-io=z:i9 *, to find x* Ans. iVzzip. 



2. Given ;f* — x— 4011:170 j to find X. Ans. KZizi^. 



3. Given 3;?*-j-2;v — 9=7<^ j to find ;v. Ans. a:^:^. 



4. Given '• (-741=: 20 ; to find ic. 



2 3 



Ans. A;zr5-4093, 3cc. 



5. Give'n ^f'-j-Arra ; to find ;c. 



Ans. x-=i^a'\^\ — |, 

 ^. Given x * -j-^?;; — h-^rzc ; to find ;v. 



Ang. piZZsj cArbA ■ • 



X X 7. Given 



