\(15x=5y=3z\)
\(\Leftrightarrow\dfrac{x}{2}=\dfrac{y}{6}=\dfrac{z}{10}\)
\(\Leftrightarrow\dfrac{2x}{4}=\dfrac{y}{6}=\dfrac{z}{10}=\dfrac{2x-y-z}{4-6-10}=\dfrac{3}{2}\)(t/c dãy tỉ số bằng nhau)
=> \(\left\{{}\begin{matrix}x=3\\y=9\\z=15\end{matrix}\right.\)