$\dfrac{x+2020}{2}+\dfrac{2x+4040}{7}=\dfrac{x+2020}{5}+\dfrac{x+2020}{6}$
$\dfrac{x+2020}{2}+\dfrac{2.(x+2020)}{7}-\dfrac{x+2020}{5}-\dfrac{x+2020}{6}=0$
$(x+2020)(\dfrac{1}{2}+\dfrac{2}{7}-\dfrac{1}{5}-\dfrac{1}{6})=0$
Vì $\dfrac{1}{2}+\dfrac{2}{7}-\dfrac{1}{5}-\dfrac{1}{6}>0$
$→x+2020=0$
$→x=-2020$
Vậy $x=-2020$