Tham khảo
`3(x-2)=18-(6+x)`
`⇒3x-6=18-6-x`
`⇒3x-6=12-x`
`⇒4x-6=12`
`⇒4x=18`
`⇒x=\frac{9}{2}`
`b) \frac{2}{5}(x-\frac{1}{2}x)=\frac{1}{5}+2x`
`⇒\frac{2}{5}x-\frac{1}{5}x=\frac{1}{5}+2x`
`⇒\frac{1}{5}x=\frac{1}{5}+2x`
`⇒\frac{-9}{5}x=\frac{1}{5}`
`⇒x=\frac{-1}{9}`
`c) \frac{2}{5}.(1-\frac{1}{2}x)=\frac{2}{5}.(\frac{1}{3}+\frac{10}{3}x)`
`⇒1-\frac{1}{2}x=\frac{1}{3}+\frac{10}{3}x`
`⇒\frac{2}{3}=\frac{1}{2}x+\frac{10}{3}x`
`⇒\frac{2}{3}=\frac{23}{6}x`
`⇒x=\frac{4}{23}`
`\text{©CBT}`