`#huy`
`(x.y)/(2.5)=x/2=y/5`
`(x/2)^2=x/2 . x/2=x/2 . y/5=(x.y)/(2.5)=10/10=1`
`<=>(x/2)^2=1^2<=>`\(\left[ \begin{array}{l}\dfrac{x}{2}=1\\\dfrac{x}{2}=-1\end{array} \right.\) `<=>`\(\left[ \begin{array}{l}x=2\\x=-2\end{array} \right.\)
Voiws `x=2` thay `x.y=10`
`2.y=10`
`y=10:2=5`
Với `x=-2` thay `x.y=10`
`-2.y=10`
`y=10:(-2)=-5`
Vậy `x=2` thì `y=5`
`x=-2` thì `y=-5`
