làm nhanh giúp e ạ, cảm ơn

`#Chanh`

`b) x/10 = 7/10 + ( - 13)/20`

`x/10 = 14/20 + (  - 13)/20`

`x/10 = ( 14 + ( - 13))/20`

`x/10 = 1/20`

`x. 20 = 10. 1`

`20x = 10`

`x = 10/20`

`x = 1/2`

Vậy : `x = 1/2`