Answer:
-3x^7y^5
Explanation:
I assume the number 3 after parentheses is an exponent. I also assume that 4 after x and 2 after y are exponents. If so, please use the symbol ^ to show clearly it's an exponent.
(xy)^3 · (-3x^4y^2) =
= x^3 * y^3 * (-3x^4y^2)
= -3x^7y^5