Bài 2. (1,5 điểm) Tìm x, biết: a) $\frac{2}{3}$x - 0,5 = $\frac{3}{4}$ b) $\frac{1}{3}$ - |$\frac{3}{4}$ - x| = $\frac{1}{12}$ c) $\frac{3}{x - 2}$ = $\frac{-2}{x - 4}$

`Accnswer`

`a)`

`2/3 x - 0,5 = 3/4`

`=>2/3 x = 3/4 + 1/2`

`=>2/3 x = 5/4`

`=>x = 5/4 : 2/3`

`=>x = 15/8`

Vậy `x = 15/8`

`b)`

`1/3 - | 3/4 - x | = 1/12`

`=>| 3/4 - x | = 1/3 - 1/12`

`=>| 3/4 - x| = 1/4`

`@TH_1:`

`3/4 - x = 1/4` 

`=> x=  3/4 -1 /4`

`=> x = 1/2` 

`@TH_2:`

`3/4 - x= -1/4`

`=>x = 3/4 + 1/4`

`=>x=1`

Vậy `x in {1/2; 1}`

`c)`

`3/(x -2) = -2/(x -4) (đk: {(x!=2),(x!=4):})`

`=> 3(x -4) = -2(x -2)`

`=> 3x - 12 = -2x + 4`

`=> 3x - 12 + 2x = 4`

`=> 5x -12  = 4`

`=> 5x = 16`

`=> x= 16/5(TM)`

Vậy `x=  16/5`