Answer
$-20x^{2}y$
Work Step by Step
We are given the expression $(4xy)(-5x)$.
$(4xy)\times(-5x)=(4\times-5)\times(x\times x)\times(y)$
We can use the product rule to simplify the middle term, which holds that $a^{m}\times a^{n}=a^{m+n}$.
Therefore, $(4\times-5)\times(x\times x)\times(y)=-20\times x^{1+1}\times y=-20x^{2}y$
