Ответ:

[tex] - \frac{4}{9} [/tex]

Пошаговое объяснение:

[tex] - \frac{4}{7} \times \frac{7}{9} = - 4 \times \frac{1}{9} = - \frac{4}{1} \times \frac{1}{9} = - \frac{4 \times 1}{1 \times 9} = - \frac{4}{9} [/tex]

[tex] - \frac{4}{7} \times \frac{7}{9} = - \frac{4 \times 7}{7 \times 9} = - \frac{4 \times 1}{1 \times 9} = - \frac{4}{9} [/tex]