Tìm x a) x + 3/4 = -1/12 b) | 3/8 – x | = 5/6 c) x+5 / 6 = -2/3 d) -3/4 : ( 2 và 1/4 . x – 25% ) = 3

`\text{a)}`

`x +3/4 = {-1}/12`

`-> x = {-1}/12 -3/4`

`-> x = {-1}/12 – 9/12`

`-> x = {-5}/6`

Vậy `x  = {-5}/6`

`\text{b)}`

`|3/8-x| =5/6`

`->` \(\left[ \begin{array}{l}\dfrac{3}{8}- x = \dfrac{5}{6}\\\dfrac{3}{8}- x = \dfrac{-5}{6}\end{array} \right.\) 

`->` \(\left[ \begin{array}{l}x= \dfrac{-11}{24}\\x= \dfrac{29}{24}\end{array} \right.\) 

Vậy `x \in { {-11}/24 ; 29/24 }`

`\text{c)}`

`x +5/6 = {-2}/3`

`-> x = {-2}/3 – 5/6`

`-> x = {-3}/2`

Vậy `x = {-3}/2`

`\text{d)}`

`{-3}/4 : (2 1/4x – 25% ) =3`

`-> {-3}/4 : ( 9/4x – 1/4 ) =3`

`-> 9/4x – 1/4 = {-3}/4 . 1/3`

`-> 9/4x -1/4 = {-1}/4` 

`-> 9/4x =0`

`-> x =0` 

Vậy `x =0`