`\text{~~Holi~~}`
`a/`
`(x-2)(y-3)=5`
`->`\(\left[ \begin{array}{l}x-2=5\\y-3=5\end{array} \right.\)
`->`\(\left[ \begin{array}{l}x=7\\y=8\end{array} \right.\)
`\text{Vậy}` `x=7`, `y=8`
`b/`
`(1-x)(y+1)=3`
`->`\(\left[ \begin{array}{l}1-x=3\\y+1=3\end{array} \right.\)
`->`\(\left[ \begin{array}{l}x=-2\\y=2\end{array} \right.\)
`\text{Vậy}` `x=-2`, `y=2`