Ta có :
\(A=8x-4⋮B=2x+3\)
Mà \(B=2x+3⋮B=2x+3\)
\(\Leftrightarrow\left\{{}\begin{matrix}8x-4⋮2x+3\\8x+12⋮2x+3\end{matrix}\right.\)
\(\Leftrightarrow16⋮2x+3\)
\(\Leftrightarrow2x+3\inƯ\left(16\right)\)
\(\Leftrightarrow\left[{}\begin{matrix}2x+3=1\\2x+3=4\\2x+3=16\end{matrix}\right.\) \(\Leftrightarrow\left[{}\begin{matrix}x=-1\\x=\dfrac{1}{2}\\x=\dfrac{13}{2}\end{matrix}\right.\)
Vậy ..