Đáp án:
Giải thích các bước giải:
1) $ x.y=17 =17.1=1.17=(-1).(-17)=(-17).(-1)$
Vậy: $(x;y)=\left \{ (1;17),(17;1),(-1;-17),(-17;-1) \right \}$
2) $x.y=13=1.13=13.1=(-1).(-13)=(-13).(-1)$
Vậy: $(x;y)=\left \{ (1;13),(13;1),(-1;-13),(-13;-1) \right \}$
3) $(x-1)(6-y)=5=5.1=1.5=(-1).(-5)=(-5).(-1)$
TH1: $\left\{\begin{matrix}
x-1=1 & & \\
6-y=5 & &
\end{matrix}\right.\Rightarrow \left\{\begin{matrix}
x=2 & & \\
y=1 & &
\end{matrix}\right.$
TH2: $\left\{\begin{matrix}
x-1=-1 & & \\
6-y=-5 & &
\end{matrix}\right.\Rightarrow \left\{\begin{matrix}
x=0 & & \\
y=11 & &
\end{matrix}\right.$
TH3: $\left\{\begin{matrix}
x-1=-5 & & \\
6-y=-1 & &
\end{matrix}\right.\Rightarrow \left\{\begin{matrix}
x=-4 & & \\
y=7& &
\end{matrix}\right.$
TH4: $\left\{\begin{matrix}
x-1=5 & & \\
6-y=1 & &
\end{matrix}\right.\Rightarrow \left\{\begin{matrix}
x=6 & & \\
y=5& &
\end{matrix}\right.$
Vậy $(x;y)=\left \{ (2;1),(0;11);(-4;7),(6;5) \right \}$
