\(5x\left(x-2020\right)-2x+4040=0\)
\(\Rightarrow5x\left(x-2020\right)-2\left(x-2020\right)=0\)
\(\Rightarrow\left(x-2020\right)\left(5x-2\right)=0\)
\(\Rightarrow\left\{{}\begin{matrix}x-2020=0\\5x-2=0\end{matrix}\right.\Rightarrow\left\{{}\begin{matrix}x=2020\\x=\dfrac{2}{5}\end{matrix}\right.\)
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