Question

Giải các phương trình sau:

a) 5x−(2−4x)=6+3(x−1)

b) \(\frac{{x - 1}}{4}\)+2x=3 - \(\frac{{2{\rm{x}} - 3}}{3}\)

Answer 1

`5x-(2-4x) =6+3(x-1)`

`<=> 5x-2+4x=6+3x-3`

`<=> 5x+4x-3x=6-3+2`

`<=> 4x=5`

`<=>x=5/4`

Vậy \(S=\left\{\dfrac{5}{4}\right\}\)

__

\(\dfrac{x-1}{4}+2x=3-\dfrac{2x-3}{3}\\ \Leftrightarrow\dfrac{3\left(x-1\right)}{12}+\dfrac{2x\cdot12}{12}=\dfrac{3\cdot12}{12}-\dfrac{4\left(2x-3\right)}{12}\\ \Leftrightarrow3x-3+24x=36-8x+12\\ \Leftrightarrow3x+24x+8x=36+12+3\\ \Leftrightarrow35x=51\\ \Leftrightarrow x=\dfrac{51}{35}\)

Vậy \(S=\left\{\dfrac{51}{35}\right\}\)