Question

A square matrix A has 9 elements. What is the possible order of A?

• A. $1\times 9$
• B. $9\times 9$
• C. $3\times 3$
• D. $2\times 7$

Answer 1

The correct option is C $3\times 3$

The factors of $9$ are $1,3$ and $9$.

So, the possible orders of a matrix containing $9$ elements is $1\times 9$, $9\times 1$, $3\times 3$.

In a square matrix, the number of rows is equal to the number of columns. So, the required order is $3\times 3$.