\(\dfrac{x-2}{2016}+\dfrac{x-4}{1009}+\dfrac{x-6}{2020}=-4\)
<=>\(\dfrac{x-2}{2016}+1+\dfrac{x-4}{1009}+2+\dfrac{x-6}{2020}+1=0\)
<=>\(\dfrac{x+2014}{2016}+\dfrac{x+2014}{1009}+\dfrac{x+2014}{2020}=0\)
<=>\(\left(x+2014\right)\left(\dfrac{1}{2016}+\dfrac{1}{1009}+\dfrac{1}{2020}\right)=0\)
vì 1/2016+1/1009+1/2020 khác 0
=>x+2014=0<=>x=-2014