Ответ:
\[\frac{6x^{2}y^{2} - 24x^{3}y^{3}}{(1 - 4xy)xy^{3}} =\]
\[= \frac{6x^{2}y^{2}(1 - 4xy)}{(1 - 4xy)xy^{3}} = \frac{6x}{y}.\]
\[\frac{6x^{2}y^{2} - 24x^{3}y^{3}}{(1 - 4xy)xy^{3}} =\]
\[= \frac{6x^{2}y^{2}(1 - 4xy)}{(1 - 4xy)xy^{3}} = \frac{6x}{y}.\]