Question

7x²-7x=x²-2x+1

Answer 1

<=>7x(x-1)=(x-1)²

<=>7x(x-1)-(x-1)² =0

<=>(x-1)(7x-x+1)=0

<=>(x-1)(6x+1)=0

<=>x-1=0 hoặc 6x+1=0

<=>x=1 hoặc 6x=-1

<=>x=1 hoặc x= -1/6

Answer 2

\(7x^2-7x=x^2-2x+1\)

\(\Leftrightarrow7x\left(x-1\right)-\left(x^2-2x+1\right)=0\)

\(\Leftrightarrow7x\left(x-1\right)-\left(x-1\right)^2=0\)

\(\Leftrightarrow\left(x-1\right)\left(7x-x+1\right)\)\(=0\)

\(\Leftrightarrow\left(x-1\right)\left(6x+1\right)=0\)

\(\Leftrightarrow\orbr{\begin{cases}x-1=0\\6x+1=0\end{cases}}\Leftrightarrow\orbr{\begin{cases}x=1\\x=-\frac{1}{6}\end{cases}}\)

Vậy.........