$\left[\begin{array}{ccc} -2 &2 &1\cr 2 &4 &-1\cr 2 &4 &3\cr 2 &-2 &-5 \end{array}\right] =$ $\left[\Rule{0pt}{4.8em}{0pt}\right.$$\left]\Rule{0pt}{4.8em}{0pt}\right.$ $\left[\Rule{0pt}{3.6em}{0pt}\right.$$\left]\Rule{0pt}{3.6em}{0pt}\right.$