(Solved): 3. Use elementary row operations to transform the augmented coefficient matrix to echelon form. Th ...

3. Use elementary row operations to transform the augmented coefficient matrix to echelon form. Then solve the system by back substitution. \[ \begin{aligned} 4 x_{1}-2 x_{2}-3 x_{3}+x_{4} &=3 \\ 2 x_{1}-2 x_{2}-5 x_{3} &=-10 \\ 4 x_{1}+x_{2}+2 x_{3}+x_{4} &=17 \\ 3 x_{1}+x_{3}+x_{4} &=12 \end{aligned} \]