[tex](-3\sqrt{128})(-4\sqrt{50})\qquad \begin{cases} 128=2\cdot 2\cdot 2\cdot 2\cdot 2\cdot 2\cdot 2\\ \qquad 2^6\cdot 2\\ \qquad (2^3)^2\cdot 2\\ 50=5\cdot 5\cdot 2\\ \qquad 5^2\cdot 2 \end{cases} \\\\\\ (-3\sqrt{(2^3)^2\cdot 2})(-4\sqrt{5^2\cdot 2})\implies 12\sqrt{(2^3)^2\cdot 2}\cdot \sqrt{5^2\cdot 2} \\\\\\ 12\cdot 2^3\sqrt{2}\cdot 5\sqrt{2}\implies 12\cdot 2^3\cdot 5\cdot \sqrt{2^2}\implies 12\cdot 2^3\cdot 5\cdot 2\implies 960[/tex]
