Answer
$=-2x^3y^2-4x^3y-8$
Work Step by Step
Given:$(4x^3y^2-7x^3y-4)-(6x^3y^2-3x^3y+4)$
This implies
$(4x^3y^2-7x^3y-4)-(6x^3y^2-3x^3y+4)=4x^3y^2-7x^3y-4-6x^3y^2+3x^3y-4$
and $=4x^3y^2-6x^3y^2-7x^3y+3x^3y-4-4$
Hence, the result is : $=-2x^3y^2-4x^3y-8$