\(\Leftrightarrow\left(2x-3\right)\left(2x+7\right)< =0\)
\(\Leftrightarrow\left\{{}\begin{matrix}2x+7>=0\\2x-3< =0\end{matrix}\right.\Leftrightarrow-\dfrac{7}{2}< =x< =\dfrac{3}{2}\)
\(\Leftrightarrow\left\{{}\begin{matrix}3-2x\ge0\\2x-7\ge0\end{matrix}\right.\)
\(\Leftrightarrow\left\{{}\begin{matrix}-2x\ge-3\\2x\ge7\end{matrix}\right.\)
\(\Leftrightarrow\left\{{}\begin{matrix}x\ge\\x\ge\dfrac{7}{2}\end{matrix}\right.\dfrac{3}{2}}\)
(3-2x)(2x+7)>=0
6x +21 - 4x2 -14x >=0
-4x2 -8x +21 >=0
-7/2 <=x <=3/2
