Answer
$x^4y^2+8x^3y+y-6x$
Work Step by Step
Removing the grouping symbols and then combining like terms, the given expression, $
(3x^4y^2+5x^3y-3y)-(2x^4y^2-3x^3y-4y+6x)
,$ simplifies to
\begin{array}{l}\require{cancel}
3x^4y^2+5x^3y-3y-2x^4y^2+3x^3y+4y-6x
\\\\=
(3x^4y^2-2x^4y^2)+(5x^3y+3x^3y)+(-3y+4y)-6x
\\\\=
x^4y^2+8x^3y+y-6x
.\end{array}
