Introduction to Matrices
A matrix is a rectangular array of numbers. Matrices are used in computer graphics, solving systems of equations, and data organisation. Year 8 introduces basic matrix operations.
What You Need to Know
Key Concept Diagram
A matrix is described by its order: rows x columns (e.g. a 2x3 matrix has 2 rows and 3 columns)
Matrix addition: add corresponding elements; matrices must have the same order
Scalar multiplication: multiply every element by the scalar
Matrix multiplication is only possible when the number of columns in the first equals the rows in the second
Key Vocabulary
Matrix
A rectangular array of numbers arranged in rows and columns
Order
The dimensions of a matrix given as rows x columns
Element
An individual number in a matrix
Scalar
A single number used to multiply every element of a matrix
Knowledge Check
Select the correct answer for each question. Click "Check Answer" to see if you are right.
Question 1
A matrix with 3 rows and 2 columns has order:
Question 2
If A = [2, 4] and B = [3, 1], what is A + B?
Question 3
If matrix A = [3, 6; 1, 2] and scalar k = 2, what is 2A?
Key Concepts Summary
- ●A matrix is described by its order: rows x columns (e.g. a 2x3 matrix has 2 rows and 3 columns)
- ●Matrix addition: add corresponding elements; matrices must have the same order
- ●Scalar multiplication: multiply every element by the scalar
- ●Matrix multiplication is only possible when the number of columns in the first equals the rows in the second