`(x-3/4)(4+3x)+0`
`<=>` \(\left[ \begin{array}{l}x-\dfrac34=0\\3x+4=0\end{array} \right.\)
`<=>` \(\left[ \begin{array}{l}x=\dfrac34\\3x=-4\end{array} \right.\)
`<=>` \(\left[ \begin{array}{l}x=\dfrac34\\x=-\dfrac43\end{array} \right.\)
Vậy `x=3/4` hoặc `x=-4/3`
Ta có: \(\left(x-\dfrac{3}{4}\right)\left(3x+4\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x=\dfrac{3}{4}\\x=-\dfrac{4}{3}\end{matrix}\right.\)