WeBWorK Standalone Renderer

Find the $LU$ factorization of $A= \left[\begin{array}{cc} 1 &-3\cr -3 &12 \end{array}\right]$ and use it to solve the system $\left[\begin{array}{cc} 1 &-3\cr -3 &12 \end{array}\right] \left[\begin{array}{c} x_{1}\cr x_{2}\cr \end{array}\right] = \left[\begin{array}{c} 14\cr -51 \end{array}\right].$

$A = LU =$ $\left[\Rule{0pt}{2.4em}{0pt}\right.$ $\left]\Rule{0pt}{2.4em}{0pt}\right.$ $\left[\Rule{0pt}{2.4em}{0pt}\right.$ $\left]\Rule{0pt}{2.4em}{0pt}\right.$

$\vec{x} =$ $\left[\Rule{0pt}{2.4em}{0pt}\right.$ $\left]\Rule{0pt}{2.4em}{0pt}\right.$

You can earn partial credit on this problem.