Giúp mik vs ak trước 8h

Đáp án:

Giải thích các bước giải:

 `a) 2/5 - x = 1/2`

              `x=2/5-1/2`

               `x=-3/10`

`b)|x-2/3| - 1= 5/3`

          `|x-2/3|= 5/3 + 1`

          `|x-2/3|=8/3`

`=>{(x- 2/3 = 5/3),(x-2/3=-5/3):}` $\\$ `=>{(x=5/3+2/3), (x=5/3+(-5/3)):}` $\\$ `=>{(x=7/3),(x=0):}`

$\text{ vậy x= 7/3 hoặc x=0}$

`c) (x+1)/(-2)=(-2)/(x+1)`

`=>2^2 = (x+1)^2`

`=>{(x+1=2),(x+1=-2):}` $\\$ `=>{(x=2-1),(x=(-2)-1):}` $\\$ `=>{(x=1),(x=-3):}` $\\$ $\text{x=1 hoặc x=-3}$

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Làm lại ạ:

`a) 2/5 - x = 1/2`

` x = 2/5 - 1/2`

` x = 4/10 - 5/10`

` x = -1/10`

Vậy `x = -1/10`

`b) | x - 2/3| - 1 = 5/3`

` |x-2/3| = 5/3 + 1 `

` |x-2/3} = 8/3`

`TH1 : x - 2/3 = 8/3`

` x = 8/3 + 2/3`

` x = 10/3`

`TH2 : x - 2/3 = -5/3`

` x = -5/3 + 2/3`

`-> x = -1`

Vậy `x in {10/3 ; -1}`

`c)`$\dfrac{x+1}{-2}$ `=` $\dfrac{-2}{x+1}$

` (x+1).(x+1) = (-2).(-2) `

` (x-1)^2 = (-2)^2`

` TH1 : x + 1 = 2`

` x = 2 11 `

` x = 1`

`TH2 : x + 1 = -2`

` x = -2 -1`

` x = -3`

Vậy `x in {1;-3}`