2 câu trả lời
`@` Tham khảo `@`
`3.(x-1)= 12`
`x-1= 12:3`
`x-1= 4`
`x= 4+1`
`x= 5`
Vậy `x= 5`
`#Jo`
$3\cdot \left(x-1\right)=12$
$⇒x-1=12:3$
$⇒x-1=4$
$⇒x=4+1$
$⇒x=5$
`Vậy` $x=5$
`@` Tham khảo `@`
`3.(x-1)= 12`
`x-1= 12:3`
`x-1= 4`
`x= 4+1`
`x= 5`
Vậy `x= 5`
`#Jo`
$3\cdot \left(x-1\right)=12$
$⇒x-1=12:3$
$⇒x-1=4$
$⇒x=4+1$
$⇒x=5$
`Vậy` $x=5$