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

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

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

\begin{equation}10x^{4}y+5x^{3}y^{2}-9x^{2}y^{3}-(7x^{4}y+8x^{3}y^{2}-2xy)\end{equation}

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

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

\begin{equation}7A^{2}+6Ay+y-((-4)A^{2}+5Ay-8y)\end{equation}

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

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

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

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