Two numbers that represent the number of rows and the number of columns in a matrix.
The term “dimensions” of a matrix is a synonym for the size of the matrix.
If a matrix has 3 rows and 5 columns, then its dimensions are 3 by 5.
Example
The dimensions of this matrix are 3 by 5:
\(\begin{bmatrix}
2 & 5 & -2 & 7 & 10 \\
1 & -1 & 0 & 2 & -2 \\
-3 & 0 & 3 & 5 & 12
\end{bmatrix}\)