Question

2 x² - \(\dfrac{2}{7}\)x = 0

Answer 1

\(2x^2-\dfrac{2}{7}x=0\)

\(\Rightarrow x\left(2x-\dfrac{2}{7}\right)=0\)

\(\Rightarrow\left\{{}\begin{matrix}x=0\\2x-\dfrac{2}{7}=0\Rightarrow2x=\dfrac{2}{7}\Rightarrow x=\dfrac{1}{7}\end{matrix}\right.\)

Answer 2

2x² - \(\dfrac{2}{7}\)x = 0

\(\Rightarrow\) x(2x - \(\dfrac{2}{7}\)) = 0

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

Vậy x \(\in\left\{0;\dfrac{1}{7}\right\}\)