Question

(x-1)x(y+2)=7

 

Answer 1

\(\left(x-1\right)\left(y+2\right)=7=1.7=7.1=\left(-1\right).\left(-7\right)=\left(-7\right)\left(-1\right)\)

Xét 4 trường hợp ,ta có :

\(\left(1\right)\hept{\begin{cases}x-1=1\\y+2=7\end{cases}\Rightarrow\hept{\begin{cases}x=2\\y=5\end{cases}}}\)

\(\left(2\right)\hept{\begin{cases}x-1=7\\y+2=1\end{cases}\Rightarrow\hept{\begin{cases}x=8\\y=-1\end{cases}}}\)

\(\left(3\right)\hept{\begin{cases}x-1=-1\\y+2=-7\end{cases}\Rightarrow\hept{\begin{cases}x=0\\y=-9\end{cases}}}\)

\(\left(4\right)\hept{\begin{cases}x-1=-7\\y+2=-1\end{cases}\Rightarrow\hept{\begin{cases}x=-6\\y=-3\end{cases}}}\)