To simplify the expression, first distribute the -4/9x^5y^7 to both terms in the second expression:
(-4/9x^5y^7) * (6 3/4xy^4)
= (-4/9 6 3/4) (x^5 x) (y^7 y^4)= (-4/9 27/4) x^6 y^11= (-108/36) x^6 y^11= -3 x^6 y^11
Therefore, the simplified expression is -3x^6y^11.
To simplify the expression, first distribute the -4/9x^5y^7 to both terms in the second expression:
(-4/9x^5y^7) * (6 3/4xy^4)
= (-4/9 6 3/4) (x^5 x) (y^7 y^4)
= (-4/9 27/4) x^6 y^11
= (-108/36) x^6 y^11
= -3 x^6 y^11
Therefore, the simplified expression is -3x^6y^11.