\(\frac{x+5}{2017}+\frac{x+6}{2016}+\frac{x+7}{2015}=-3\)
\(\left(\frac{x+5}{2017}+1\right)+\left(\frac{x+6}{2016}+1\right)+\left(\frac{x+7}{2015}+1\right)=0\)
\(\frac{x+2022}{2017}+\frac{x+2022}{2016}+\frac{x+2022}{2015}=0\)
\(\left(x+2022\right)\left(\frac{1}{2017}+\frac{1}{2016}+\frac{1}{2015}\right)=0\)
\(x+2022=0\left(\frac{1}{2017}+\frac{1}{2016}+\frac{1}{2015}\ne0\right)\)
x=-2022