Answer
$\left[\begin{array}{ccc}
2-4x & -6 & -4w\\
-4z & 4-4r & -18
\end{array}\right]$
Work Step by Step
$A=\left[\begin{array}{lll}
1 & -1 & 0\\
0 & 2 & -1
\end{array}\right],\quad B=\left[\begin{array}{lll}
3 & 0 & -1\\
5 & -1 & 1
\end{array}\right],\quad C=\left[\begin{array}{lll}
x & 1 & w\\
z & r & 4
\end{array}\right]$
$(2A-4C)_{ij}=2\cdot a_{ij}-4\cdot c_{ij}$
-----
$2A-4C=\left[\begin{array}{lll}
2(1)-4(x ) & 2(-1)-4(1 ) & 2(0)-4(w )\\
2(0)-4(z ) & 2(2)-4( r) & 2(-1)-4(4 )
\end{array}\right]$
$=\left[\begin{array}{lll}
2-4x & -6 & -4w\\
-4z & 4-4r & -18
\end{array}\right]$
