Tìm x: a) $\frac{x}{3}$ - $\frac{2x + 1}{2}$ = $\frac{x}{6}$ - x b) $\frac{2 + x}{5}$ - 0,5x = $\frac{1 - 2x}{4}$ +0,25 c) $\frac{2x - 1}{4}$ + 3 = $\frac{1 - 3x}{6}$

`text{Đáp án + Giải thích các bước giải :}`

`a) x/3 - (2x+1)/2 = x/6 - x`

`x/3 . 6 - (2x+1)/2 . 6 = x/6 . 6 - x . 6`

`2x - 6x - 3 = -5x`

`-4x - 3 = -5x`

`-4x = -5x + 3`

`-4x + -5x =  -5x + 3 + -5x`

`=>` `x = 3 .`

Vậy `x = 3 .`

`b) (2+x)/5 - 0,5x = (1-2x)/4 + 0,25`

`(2+x)/5 . 100 - 0,5x . 100 = (1-2x)/4 . 100 + 0,25 . 100`

`20(x + 2) - 50x = 25(-2x + 1) + 25`

`-30x + 40 = -50x + 50`

`-30x = -50x + 50 - 40`

`-30x = -50x + 10`

`-30x + 50= -50x + 10 + 50x`

`20x = 10`

`x = 10 : 20`

`=>` `x = 1/2 .`

Vậy `x = 1/2 .`

`c) (2x-1)/4 + 3 = (1-3x)/6`

`(2x-1)/4 . 12 + 3 . 12 = (1-3x)/6 . 12`

`3(2x - 1) + 36 = 2(-3x + 1)`

`6x + 33 = -6x + 2`

`6x = -6x + 2 - 33`

`6x = -6x - 31`

`12x = -6x - 31 + 6x`

`12x = -31`

`x = 31 : 12`

`=>` `x = 31/12 .`

Vậy `x = 31/12 .`

`text{#Muối}`