dividing a fraction is the same as multiplying by the reciprocal.
[tex] \frac{3}{5} [/tex]÷[tex] \frac{-4}{9} [/tex] = [tex] \frac{3}{5} [/tex]x[tex] \frac{-9}{4} [/tex] = [tex] \frac{3 x -9}{5 x 4} [/tex] = [tex] \frac{-27}{20} [/tex]