\(\frac{x}{-3}=\frac{y}{-7}\)
áp dụng t/c dãy tỉ số bằng nhau, ta có:
\(\frac{x}{-3}=\frac{y}{-7}=\frac{2x}{-6}=\frac{4y}{-28}=\frac{2x+4y}{-6+\left(-28\right)}=\frac{64}{-34}=\frac{32}{-17}\)
\(x=\frac{-3.32}{-17}=\frac{96}{17}\)
\(y=\frac{-7.32}{-17}=\frac{224}{17}\)