a) \(\left(3x-2\right)\left(\frac{10x\left(x+3\right)-7\left(4x-3\right)}{35}\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}3x-2=0\\-18x+51=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=\frac{2}{3}\\x=\frac{17}{6}\end{matrix}\right.\)
b)\(\left(3,3x-11\right)\left(\frac{3\left(7x+2\right)+10\left(1-3x\right)}{15}\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x=\frac{3}{10}\\x=\frac{16}{9}\end{matrix}\right.\)