Question

\(\frac{x}{2}=\frac{y}{3}\)và\(x.y=54\)

Answer 1

x=6

y=9

Answer 2

x=6

y=9

Answer 3

\(\frac{x}{2}=\frac{y}{3}\Rightarrow\frac{xy}{2}=\frac{y^2}{3}=\frac{54}{2}=27\)

\(\Rightarrow y^2=81\)

\(\Rightarrow\orbr{\begin{cases}y=9\\y=-9\end{cases}}\)

Với y=9 thì x=6

Với y=-9 thì x=-6

Answer 4

đặt \(\frac{x}{2}=\frac{y}{3}=k\Rightarrow x=2k;y=3k\)

Mà \(xy=54\)hay  \(2k\cdot3k=54\)

                       \(\Leftrightarrow6k^2=54\)

                        \(\Leftrightarrow k^2=9\)

                        \(\Leftrightarrow\orbr{\begin{cases}k=-3\\k=3\end{cases}}\)

Nếu \(k=-3\)thì \(x=2k=-6;y=3k=-9\)

Nếu \(k=3\)thì \(x=2k=6;y=3k=9\)