\(3x+2\inƯ\left(9\right)=\left\{\pm1;\pm3;\pm9\right\}\)
Ta có bảng sau:
\(3x+2\) | \(1\) | \(-1\) | \(3\) | \(-3\) | \(9\) | \(-9\) |
\(x\) | \(\dfrac{-1}{3}\) | \(-1\) | \(\dfrac{1}{3}\) | \(\dfrac{-5}{3}\) | \(\dfrac{7}{3}\) | \(\dfrac{-11}{3}\) |
Mà \(x\in Z\Rightarrow x=-1\)