Đặt \(k=\frac{x}{2}=\frac{y}{5}\)
Khi đó : \(k^2=\frac{xy}{2.5}=\frac{90}{10}=9\)
Suy ra : \(k=-3;3\)
+ k = -3 thì : \(\frac{x}{2}=-3\Rightarrow x=-6\)
\(\frac{y}{5}=-3\Rightarrow y=-15\)
+ k = 3 thì : \(\frac{x}{2}=3\Rightarrow x=6\)
\(\frac{y}{5}=3\Rightarrow y=15\)