Ta có: \(3x=7y\)
\(\Rightarrow\frac{x}{7}=\frac{y}{3}=\frac{y-x}{3-7}=\frac{8}{-4}=-2\)
\(\Rightarrow\hept{\begin{cases}x=-14\\y=-6\end{cases}}\)
\(\frac{x+2}{3}=\frac{y-1}{4}=\frac{z+3}{5}\)
\(=\frac{x+2-y+1+z+3}{3-4+5}\)
\(=\frac{x-y+z+6}{4}=\frac{66}{4}=16,5\)
\(\Rightarrow x,y,z=....\)