\(\Leftrightarrow\left[{}\begin{matrix}\left\{{}\begin{matrix}2-3x\ge0\\2-3x< 7\end{matrix}\right.\\\left\{{}\begin{matrix}2-3x< 0\\3x-2< 7\end{matrix}\right.\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}\left\{{}\begin{matrix}x\le\dfrac{2}{3}\\x>-\dfrac{5}{3}\end{matrix}\right.\\\left\{{}\begin{matrix}x>\dfrac{2}{3}\\x< \dfrac{5}{3}\end{matrix}\right.\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}-\dfrac{5}{3}< x\le\dfrac{2}{3}\\\dfrac{2}{3}< x< \dfrac{5}{3}\end{matrix}\right.\)
\(\Rightarrow-\dfrac{5}{3}< x< \dfrac{5}{3}\)
Vậy ....
2 - 3x < 7
\(\Leftrightarrow\left\{{}\begin{matrix}2-3x< 7\\3x-2< 7\end{matrix}\right.\Leftrightarrow\left\{{}\begin{matrix}-3x< 5\\3x< 9\end{matrix}\right.\)
\(\Leftrightarrow\) \(\left\{{}\begin{matrix}x>-\dfrac{5}{3}\\x< 3\end{matrix}\right.\)
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