Question

x(x-3)=3-x

Answer 1

=>x(x-3)-(3-x)=0

=>x(x-3)-(-x+3)=0

=>x(x-3)+(x-3)=0

=>(x+1)(x-3)=0

<=>x+1=0 hoặc x-3=0

<=>x=-1 hoặc x=3

Answer 2

= 3

Answer 3

`x(x-3)=3-x`

`=>x^2-3x-3+x=0`

`=>x^2+x-3x-3=0`

`=>x(x+1)-3(x+1)=0`

`=>(x-3)(x+1)=0`

\(=>\left[{}\begin{matrix}x-3=0\\x+1=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=3\\x=-1\end{matrix}\right.\)

Answer 4