`5.(x-3)-3(x+1)=-12`
`5x-15-3x-3=-12`
`2x-18=-12`
`2x=6`
`x=3`
Vậy `x=3`
`5 (x-3) - 3(x+1)=-12`
`<=> 5x-15 -(3x+3)=-12`
`<=>5x-15 -3x-3=-12`
`<=>2x - 18=-12`
`<=>2x= 6`
`<=>x=3`
vậy phương trình có nghiệm `x=3`
\(5\left(x-3\right)-3\left(x+1\right)=-12\\ 5x-15-3x-3=-12\\ 5x-3x-\left(15+3\right)=-12\\ 2x-18=-12\\ 2x=-12+18\\ 2x=6\\ x=3\)