nnao nua aa.......

`e,-2/5+4/5 x =3/5`

`=>4/5 x =3/5 - (-2/5)`

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

`=>4/5 x = 5/5`

`=> 4/5 x=1`

`=>x=1: 4/5`

`=>x=1 . 5/4`

`=>x=5/4`

Vậy `x=5/4`

`color{skyblue}{Cow}`