\(\left(\frac{-2}{3x}-\frac{3}{5}\right)\left(\frac{3}{-2}-\frac{10}{3}\right)\)
\(=\left[-\left(\frac{2}{3x}+\frac{3}{5}\right)\right]\left[-\left(\frac{3}{2}+\frac{10}{3}\right)\right]\)
\(=\left(\frac{2}{3x}+\frac{3}{5}\right)\left(\frac{3}{2}+\frac{10}{3}\right)\)
\(=\left(\frac{10}{15x}+\frac{9x}{15x}\right)\left(\frac{9}{6}+\frac{20}{6}\right)\)
\(=\frac{10+9x}{15x}.\frac{9+20}{6}\)
\(=\frac{29.\left(10+9x\right)}{90}\)