4800/x-4800/x+100=8

~ Bạn tham khảo ~

`4800/x - 4800/[x+100] = 8`

ĐK : `x\ne0;x\ne-100`

`<=> [4800(x+100)]/[x(x+100)] - [4800x]/[x(x+100)] = [8x(x+100)]/[x(x+100)]`

`<=> 4800(x+100) - 4800x = 8x(x+100)`

`<=> 4800x + 480000 - 4800x = 8x^2 + 800x` 

`<=> 8x^2 + 800x - 480000 = 0`

`<=> 8(x-200)(x+300) = 0`

\(⇔\left[ \begin{array}{l}x=200\quad(TMĐK)\\x=-300\quad(TMĐK)\end{array} \right.\)

Vậy `S={200;-300}`