Given the augmented matrix below, solve the associated system of equations. For your variables, use $x1$, $x2$, $x3$, $x4$, $x5$, and $x6$.
$$\displaystyle\left[\begin{array}{rrrrrr|r} 1 &-6 &5 &9 &1 &-5 &4 \cr 0 &0 &1 &4 &-2 &2 &5 \cr 0 &0 &0 &0 &1 &-2 &1 \cr \end{array}\right]$$

The solution is (,,, ,,)