Question

7 (x-1) + 2x (1-x) = 0

Answer 1

\(7\left(x-1\right)+2\left(1-x\right)=0\)

=>\(7\left(x-1\right)-2\left(x-1\right)=0\)

=>\(5\left(x-1\right)=0\)

=>\(x-1=0\)

=>\(x=1\)

Vậy....

Answer 2

\(7\left(x-1\right)+2x\left(1-x\right)=0\)

\(\Rightarrow7\left(x-1\right)-2x\left(x-1\right)=0\)

\(\Rightarrow\left(7-2x\right)\left(x-1\right)=0\)

\(\Rightarrow\left[{}\begin{matrix}7-2x=0\\x-1=0\end{matrix}\right.\)

\(\Rightarrow\left[{}\begin{matrix}x=\dfrac{7}{2}\\x=1\end{matrix}\right.\)