Matrices Quiz

What is the entry at a_2,3

• -7

• -5

• 5

• -1

• 1

Answer explanation

The entry at a_2,3 corresponds to the value in the second row and third column of the matrix. The correct value is -7, which is the only option that matches this position.

Identify the square matrix

• A

• B

• C

• D

Answer explanation

A square matrix has the same number of rows and columns. Choice B meets this criterion, while the others do not. Therefore, B is the correct answer.

M is a 3x2 matrix. How many columns does M have?

• 3

• 2

Answer explanation

M is described as a 3x2 matrix, where the first number indicates the number of rows and the second number indicates the number of columns. Therefore, M has 2 columns.

To add or subtract two matrices A and B, what must the dimensions of the two matrices be?

• A must have the same number of rows as B and the same number of columns as B

• The number of columns in A must be the same as the number of rows in B.

• The number of rows in A must be the same as the number of columns in B

• Both A and B must be square matrices

Answer explanation

To add or subtract two matrices A and B, they must have the same dimensions. This means A must have the same number of rows and columns as B, making the first answer choice correct.

How many elements does a matrix with 4 rows and 5 columns contain? (enter your answer as a number only)

Answer explanation

A matrix with 4 rows and 5 columns will have 20 elements in total (4 x 5 = 20).

If a column matrix contains 6 elements, how many rows does the matrix have? (enter your answer as a number only)

Answer explanation

A column matrix has only one column, so all 6 elements must be in their own row. Therefore there are 6 rows.

What is the order of this matrix?

• 3 x 1

• 1 x 3

Answer explanation

The order of a matrix is defined by its dimensions: rows x columns. Here, the matrix has 1 row and 3 columns, making the correct order 1 x 3.

What is the order of this matrix?

(Enter your answer in the form a x b where a and b are numbers e.g. 2 x 3)

At which element is the -1 located?

• a_2,2

• a_2,3

• a_1,3

• a_3,2

Answer explanation

The -1 is in the third row and the second column, therefore it is located at a_3,2.

Identify the row matrix

• A

• B

• C

• D

Answer explanation

A row matrix is defined as a matrix with only one row. Among the options, B is the only choice that fits this definition, making it the correct answer.