SIMPLE EQUATIONS, 33^ 



4. Let 3^* — ioA:zr8A;4-^'* be gvveiv; to find;;. 



First, 2^ — I03=:8-|-a; 

 An4 then 3 a; — ;)czz:8-f-io 

 Therefore ix^z 1 8, and xz=: V^ —9'' 



5. Given 6ax^ — i2^^A;*=3^/v^4"-6^i?tf-* *, to find x* 



First, dividing the whole by 3^/^'*, \vb shall have. 

 2X — ^^hzzX-{-2 ^ 



And then 2x — Xznl-f^h 

 Whence a;iz:2-{-4^' 



X ' X X 



6. Let -I rz: 10 be given ; to find ^* 



234 



2X 2X 



• First, ^ + — = 20 



3*4 



And then 3X' — 2x-\ r:6o » ^ 



And i2;c — 8?^4"<^^'~240 

 Therefore ioArz=:240 

 And a;:=:^V-:24. 



AT— 3 y- ^+^9 \» , 



♦7. Given z=2o— ; to find ^ 



2*3 2 



2X 

 First, X — 3-] = 40 — X — 19 



And then 3A? — 9-}-2Arzz:i2o — 3.V — 57 

 And therefore 3;f+2;f-^3/scz::^i2o — 57-j"9 

 That is, 8^=72, orAr=:yi=9. 



8. Let y/y^-[-5zir:7 be given ; to find X» 



First, -^i-A?z=r7 — ^Z=2 



And then yAm2^ZZ4 



And 2;;= 1 2, or;v=yr=5. 



p. Let 

 T T 



