Reduced Row Echelon Form: \[\begin{bmatrix} 1 & 0 & 0 & -2 \\ 0 & 1 & 0 & -5 \\ 0 & 0 & 1 & 3 \end{bmatrix}\] General Solution: \[ \begin{bmatrix} x_{ 1 } \\ x_{ 2 } \\ x_{ 3 } \\ \end{bmatrix} = \qquad \begin{bmatrix} -2 \\ -5 \\ 3 \end{bmatrix} \]

Problem:

\[
\begin{bmatrix} 
4 & -2 & -3 & -7   \\ 
2 & -3 & 3 & 20   \\ 
4 & -5 & -3 & 8
\end{bmatrix}
\]

Solution:

\begin{solution}
Reduced Row Echelon Form: 
\[\begin{bmatrix} 
1 & 0 & 0 & -2   \\ 
0 & 1 & 0 & -5   \\ 
0 & 0 & 1 & 3
\end{bmatrix}\]
General Solution:
\[
\begin{bmatrix}
x_{ 1 } \\
x_{ 2 } \\
x_{ 3 } \\
\end{bmatrix} = \qquad
\begin{bmatrix} 
-2   \\ 
-5   \\ 
3
\end{bmatrix}\]

\end{solution}