`a.|2x+3|<7`
$⇔$\(\left[ \begin{array}{l}2x+3 <7\\-(2x+3)<7\end{array} \right.\)
$⇔$\(\left[ \begin{array}{l}2x +3<7\\-2x-3<7\end{array} \right.\)
$⇔$\(\left[ \begin{array}{l}2x<4\\-2x<10\end{array} \right.\)
$⇔$\(\left[ \begin{array}{l}x<2\\x>5\end{array} \right.\)
`b.|2x -3| > 5`
$⇔$\(\left[ \begin{array}{l}2x -3 >5\\-(2x -3) >5 \end{array} \right.\)
$⇔$\(\left[ \begin{array}{l}2x -3 >5\\-2x +3 > 5\end{array} \right.\)
$⇔$\(\left[ \begin{array}{l}2x>8\\-2x>2\end{array} \right.\)
$⇔$\(\left[ \begin{array}{l}x>4\\x<-1\end{array} \right.\)
#hoctot
