Math Problem Solver

A^2+3b^t-C^2,\:A=\begin{pmatrix}-1&3\\ 2&-6\end{pmatrix},\:C=\begin{pmatrix}9&7\\ 2&6\end{pmatrix},\:b=\begin{pmatrix}1&-5\\ -3&-1\end{pmatrix}