Can anyone notice any patterns that can allow for the factorisation/simplification of the expression below?
\begin{eqnarray} A = 20x_0^3y_0 + 10x_0^2[3y_0\Delta x + x_0\Delta y] + 20x_0\Delta x[x_0\Delta y + y_0\Delta x] + 5\Delta x^2[3x_0\Delta y + y_0\Delta x] + 4\Delta x^3\Delta y \end{eqnarray}
where $\Delta x\!=\!(x_1-x_0)$ and $\Delta y\!=\!(y_1-y_0)$. The above expression features in the derivation for
\begin{eqnarray} \iint_{\Omega}x^2y\ dxdy=\oint_{\partial\Omega}\frac{x^3y}{3}dy \end{eqnarray}
by Green's theorem, where $\Omega$ is an arbitrary simple polygon in the $z\!=\!0$ plane whose vertices are sorted CCW, and $\partial\Omega$ is the boundary of $\Omega$.