2x+1/3 - 7x+5/15=x-8/5

`(2x+1)/3` `-` `(7x+5)/15` `=` `(x-8)/5`

`<=>` `(2x+1)/3` `-` `(7x+5)/15` `-` `(x-8)/5` `=` `0`

`<=>` `(5.(2x+1) - (7x+5) - 3.(x-8))/15` `=` `0`

`<=>` `5.(2x+1) - (7x+5) - 3.(x-8)` `=` `0`

`<=>` `10x+5 - 7x-5 - 3x+24` `=` `0`

`<=>` `(10x-7x-3x)+(5-5 +24)` `=` `0`

`<=>` `0x+24` `=` `0` $\text{(vô nghiệm)}$

`<=>` `S` `=` `\emptyset`

$\textit{#TranDucQuangNBK}$