Perform the following matrix operation:

$\left[\begin{array}{cc} -6 &1\cr -6 &5\cr 9 &1 \end{array}\right] - \left[\begin{array}{cc} -5 &4\cr -2 &2\cr -2 &4 \end{array}\right] =$$\left[\Rule{0pt}{3.6em}{0pt}\right.$$\left]\Rule{0pt}{3.6em}{0pt}\right.$