\(a,3x\left(x-1\right)+2\left(x-1\right)=0\\ \Rightarrow\left(x-1\right)\left(3x+2\right)=0\\ \Rightarrow\left[{}\begin{matrix}x=1\\x=-\dfrac{2}{3}\end{matrix}\right.\\ b,5x\left(x+2\right)+4x+8=0\\ \Rightarrow5x\left(x+2\right)+4\left(x+2\right)=0\\ \Rightarrow\left(5x+4\right)\left(x+2\right)=0\\ \Rightarrow\left[{}\begin{matrix}x=-\dfrac{4}{5}\\x=-2\end{matrix}\right.\\ c,7x\left(x-3\right)-3x+9=0\\ \Rightarrow7x\left(x-3\right)-3\left(x-3\right)=0\\ \Rightarrow\left(x-3\right)\left(7x-3\right)=0\\ \Rightarrow\left[{}\begin{matrix}x=3\\x=\dfrac{3}{7}\end{matrix}\right.\)
\(d,2x\left(x-1\right)-x+1=0\\ \Rightarrow2x\left(x-1\right)-\left(x-1\right)=0\\ \Rightarrow\left(x-1\right)\left(2x-1\right)=0\\ \Rightarrow\left[{}\begin{matrix}x=1\\x=\dfrac{1}{2}\end{matrix}\right.\)
