Question

Tìm \(x\) 

a, \(2\left(x-3\right)-4x=0\)

b, \(x^2-2x+1=25\)

Answer 1

`2(x-3)-4x=0`

`<=> 2x-6-4x=0`

`<=> -2x-6=0`

`<=>-2x=6`

`<=>x=-3`

__

`x^2-2x+1=25`

`<=>(x-1)^2=25`

`<=> (x-1)^2 = (+- 5)^2`

\(\Leftrightarrow\left[{}\begin{matrix}x-1=5\\x-1=-5\end{matrix}\right.\\ \Leftrightarrow\left[{}\begin{matrix}x=6\\x=-4\end{matrix}\right.\)

Answer 2

a: 2(x-3)-4x=0

=>2x-6-4x=0

=>-2x-6=0

=>2x+6=0

=>2x=-6

=>x=-3

b: \(x^2-2x+1=25\)

=>\(\left(x-1\right)^2=25\)

=>\(\left[{}\begin{matrix}x-1=5\\x-1=-5\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=6\\x=-4\end{matrix}\right.\)