If $A = \begin{bmatrix}2 & 2 \\ 2 & 2\end{bmatrix}$ and $A^2 = kA$, what is $k$?

Explanation

1. 01

   $A^2 = \begin{bmatrix}8 & 8 \\ 8 & 8\end{bmatrix}$.

2. 02

   That is 4 times $A$, so $k = 4$.