\begin{equation}2x^{2}+4x-2-(2x^{2}+8)\end{equation}

\begin{equation}3x^{2}y^{2}+3xy^{3}-10y^{4}-(x^{2}y^{2}-9xy^{3}+9y-6y^{4})\end{equation}

\begin{equation}10x^{3}+4x^{2}-2x+3-(5x^{3}-8x^{2}+7x-6)\end{equation}

\begin{equation}4x^{4}y+4x^{3}y^{2}-10x^{2}y^{3}-(7x^{4}y+7x^{3}y^{2}-5xy)\end{equation}

\begin{equation}8x^{2}-6x+4-(7x^{2}+8x+9)\end{equation}

\begin{equation}6x+4-(4x^{2}-3x+6)\end{equation}

\begin{equation}5A^{2}+6Ay+y-((-6)A^{2}+9Ay-9y)\end{equation}

\begin{equation}9x^{5}-2x^{4}-4-(7x^{5}+5x^{4}-5)\end{equation}

\begin{equation}(-10)x^{4}+9x^{2}y-3x+y-((-6)x^{4}-8x^{2}y+x)\end{equation}

\begin{equation}(-4)x^{2}+7xy-10y-((-7)x^{2}-3xy+9y)\end{equation}

\begin{equation}xy-4y^{2}+2xy^{3}-(4xy^{3}+4y^{2}+10xy)\end{equation}