In $A = \begin{bmatrix}4 & -2 & 7 \\ 0 & 5 & -3 \\ 8 & 1 & 6\end{bmatrix}$, what is $a_{23}$?

Explanation

1. 01

   In $a_{23}$ the first index is the row and the second the column: row 2, column 3.

2. 02

   Row 2 is $0,\ 5,\ -3$, and its third element is $-3$.