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

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

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

\begin{equation}5x^{4}y+9x^{3}y^{2}-3x^{2}y^{3}-(10x^{4}y+5x^{3}y^{2}-3xy)\end{equation}

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

\begin{equation}5x+3-(9x^{2}-8x+2)\end{equation}

\begin{equation}2A^{2}+9Ay+y-((-9)A^{2}+7Ay-9y)\end{equation}

\begin{equation}9x^{5}-7x^{4}-9-(2x^{5}+5x^{4}-3)\end{equation}

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

\begin{equation}(-7)x^{2}+8xy-7y-((-5)x^{2}-10xy+9y)\end{equation}

\begin{equation}xy-7y^{2}+4xy^{3}-(9xy^{3}+6y^{2}+8xy)\end{equation}