Đặt \(\dfrac{x}{3}=\dfrac{y}{6}=k\Rightarrow x=3k;y=6k\)
\(xy=162\\ \Rightarrow18k^2=162\\ \Rightarrow k^2=9\\ \Rightarrow\left[{}\begin{matrix}k=3\\k=-3\end{matrix}\right.\\ \Rightarrow\left[{}\begin{matrix}x=9;y=18\\x=-9;y=-18\end{matrix}\right.\)
Ta có:\(\dfrac{x}{3}=\dfrac{y}{6}=k\)
\(\Rightarrow\left\{{}\begin{matrix}x=3k\\y=6k\end{matrix}\right.\)
mà \(x.y=162\)
\(\Rightarrow3k.6k=162\)
\(\Rightarrow18k^2=162\)
\(\Rightarrow k=3\)
\(\Rightarrow\left\{{}\begin{matrix}k=3\\k=-3\end{matrix}\right.\)
\(\Rightarrow\left\{{}\begin{matrix}\dfrac{x}{3}=\dfrac{y}{6}=3\\\dfrac{x}{3}=\dfrac{y}{6}=-3\end{matrix}\right.\)
\(\Rightarrow\left\{{}\begin{matrix}x=9;y=18\\x=-9;y=-18\end{matrix}\right.\)