From the given expression
a) The linear system of a matrix form is
[tex](AX=B)[/tex]
The linear system of the given matrix will be
[tex]\begin{gathered} 2x+y+z-4w=3 \\ x+2y+0z-7w=-7 \\ -x+0y+oz+w=10 \\ 0x+0y-z+3w=-9 \end{gathered}[/tex]
b) The entries in A of the matrix is
[tex]\begin{gathered} \text{For }a_{22}=2 \\ a_{32}=0 \\ a_{43}=-1 \\ a_{55}\text{ is undefined} \end{gathered}[/tex]
c) The dimensions of A, X and B are
[tex]\begin{gathered} A\mathrm{}X=B \\ \begin{bmatrix}{2} & 1 & {1} & -4 \\ {1} & {2} & {0} & {-7} \\ {-1} & {0} & {0} & {1} \\ {0} & {0} & {-1} & {3}\end{bmatrix}\begin{bmatrix}x{} & {} & {} & {} \\ {}y & {} & {} & {} \\ {}z & {} & {} & {} \\ {}w & {} & {} & {}\end{bmatrix}=\begin{bmatrix}3{} & {} & {} & {} \\ {}-7 & {} & {} & {} \\ {}10 & {} & {} & {} \\ {}-9 & {} & {} & {}\end{bmatrix} \end{gathered}[/tex]
