Áp dụng t/c dtsbn:
\(\dfrac{x}{2}=\dfrac{y}{3}=\dfrac{z}{6}=\dfrac{2x}{4}=\dfrac{3y}{9}=\dfrac{5z}{30}=\dfrac{2x-3y+5z}{4-9+30}=\dfrac{38}{25}\)
\(\Rightarrow\left\{{}\begin{matrix}x=\dfrac{38}{25}.2=\dfrac{76}{25}\\y=\dfrac{38}{25}.3=\dfrac{114}{25}\\z=\dfrac{38}{25}.6=\dfrac{228}{25}\end{matrix}\right.\)