Consider the matrices $\mathrm{A}=\left[\begin{array}{ll}2 & -2 \\ 4 & -2\end{array}\right]$ and $\mathrm{B}=\left[\begin{array}{ll}3 & 9 \\ 1 & 3\end{array}\right]$. If matrices P and Q are such that $\mathrm{PA}=\mathrm{B}$ and $A Q=B$, then the absolute value of the sum of the diagonal elements of $2(P+Q)$ is $\_\_\_\_$ .