Identifying Matrices and Operations: Addition, Subtraction, and Multiplication

What is the dimension of a matrix with 3 rows and 2 columns?

• 2 by 3

• 3 by 3

• 3 by 2

• 2 by 2

What is the dimension of a matrix with 2 rows and 2 columns?

• 3 by 3

• 3 by 2

• 2 by 3

• 2 by 2

How do we denote the element in the first row and first column of a matrix?

• a_1_1

• a_2_1

• a_2_2

• a_1_2

How do we denote the element in the second row and first column of a matrix?

• a_1_1

• a_2_2

• a_1_2

• a_2_1

When can two matrices be added or subtracted?

• When they have the same elements

• When they have the same dimensions

• When they have the same number of columns

• When they have the same number of rows

What happens if two matrices do not have the same dimensions when trying to add or subtract them?

• The operation is still possible

• The operation is not possible

• Only addition is possible

• Only subtraction is possible

What is the resultant matrix dimension when multiplying a 3 by 2 matrix with a 2 by 3 matrix?

• 3 by 3

• 2 by 3

• 3 by 2

• 2 by 2

What is the resultant matrix dimension when multiplying a 2 by 3 matrix with a 3 by 2 matrix?

• 2 by 2

• 3 by 3

• 3 by 2

• 2 by 3

What must be true for matrix multiplication to be possible?

• The number of rows in the first matrix must equal the number of columns in the second matrix

• The number of columns in the first matrix must equal the number of rows in the second matrix

• Both matrices must have the same dimensions

• Both matrices must be square matrices

What is the resultant matrix dimension when multiplying a 3 by 1 matrix with a 2 by 3 matrix?

• 2 by 3

• 3 by 3

• 3 by 1

• 2 by 1