`(10x-5)/18+(x+3)/12=(7x+3)/6-(12-x)/9`
`<=>(2(10x-5))/36+(3(x+3))/36=(3(7x+3))/18-(2(12-x))/18`
`<=>(20x-10+3x+9)/36=(21x+9-24+2x)/18`
`<=>(23x-1)/36=(23x-15)/18`
`<=>(23x-1)/36-(23x-15)/18=0`
`<=>(23x-1)/36-(2(23x-15))/36=0`
`<=>(23x-1-46x+30)/36=0`
`<=>(-23x+29)/36=0`
`<=>(-23x+29)*1/36=0`
`<=>-23x+29=0`
`<=>x=29/23`
`text(Vậy )S={29/23}`