If If $A =\left[\begin{array}{lll}2 & -3 & 4\end{array}\right] \quad B=\left[\begin{array}{l}3 \\ 2 \\ 2\end{array}\right]$

$X =\left[\begin{array}{lll}1 & 2 & 3\end{array}\right] \quad Y=\left[\begin{array}{l}2 \\ 3 \\ 4\end{array}\right]$

then AB + XY = 

[28]

$A =\left[\begin{array}{lll}2 & -3 & 4\end{array}\right] \quad B=\left[\begin{array}{l}3 \\ 2 \\ 2\end{array}\right]$

AB = [2 × 3 + (-3) × 2 + 4 × 2]

= [6 - 6 + 8]

AB = [8]

$X =\left[\begin{array}{lll}1 & 2 & 3\end{array}\right] \quad Y=\left[\begin{array}{l}2 \\ 3 \\ 4\end{array}\right]$

XY = [1 × 2 + 2 × 3 + 3 × 4]

= [2 + 6 + 12]

XY = [20]

So AB + XY = [28] → AB + XY is a matrix as well