Tìm x : 3/49-|x+2|=x-5

`3/49 -|x+2|=x-5` (1)

Ta có `2` trường hợp sau:

`|x+2|=x+2` nếu `x+2>=0` `⇔x>=-2`

`|x+2|=-(x+2)` nếu `x+2<0` `⇔x<-2`

TH1: Nếu `x>=-2` thì `|x+2|=x+2`

Khi đó PT (1) trở thành:

`3/49 - (x+2) =x-5`

`⇔x+2=3/49 -x +5`

`⇔-x -x=-3/49 + 2 - 5`

`⇔-2x=-3/49 + 98/49 - 245/49`

`⇔-2x=-150/49`

`⇔x=-150/49 : (-2)`

`⇔x=150/49 . 1/2`

`⇔x=150/98=75/49` `(`TMĐK`)`

TH2: Nếu `x< -2` thì `|x+2|=-(x+2)`

Khi đó PT (1) trở thành:

`3/49 - [-(x+2)] =x-5`

`⇔3/49 + x+2=x-5`

`⇔x-x= 3/49-2-5 `

`⇔0=3/49 - 98/49 - 245/49`

`⇔0=-340` `(` Vô lí `)`

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Vậy `x=75/49`