Cara mengalikan dua buah matriks ?

tergantung matriks yg digunakan matriks apa...

[tex]\left[\begin{array}{ccc}a&b\\c&d\end{array}\right]\left[\begin{array}{ccc}x\\y\end{array}\right] = \left[\begin{array}{ccc}e\\f\end{array}\right] \\ \left[\begin{array}{ccc}x\\y\end{array}\right] = \left[\begin{array}{ccc}e\\f\end{array}\right] \\ penjelasan : \\ ax + by = e \\ cd + dy = f \\ \\ A\left[\begin{array}{ccc}a&b\\c&d\end{array}\right], B \left[\begin{array}{ccc}p&q\\r&s\end{array}\right] \\ A xB= \left[\begin{array}{ccc}ap+br&aq+bs\\cp+dr&cq+ds\end{array}\right][/tex][/tex]