Matrices

• Are used by Netflix and Hulu to recommend videos for you

• Help solve higher Algebra problems such as Quadratics.

• Are used in computer graphics and video games.

A Matrix is comprised of....

• Rows

• Columns

• Elements

Size of a Matrix

The size is determined by the number of rows x number of columns. Only like size matrices can be added or subtracted from one another.

Identifying Elements in a Matrix

We use subscript to identify the location of an element in a matrix. It is the name of the matrix followed by row x column. Rows are top to bottom and columns are left to right.

Determinants

Determinant of 2 x 2 Matrix

det A = ad - bc

If the determinant of a matrix is not equal to zero, then the matrix has an inverse.

​Multiplying Matrices

Once we know we can multiply matrices, then we can start the process. First, highlight the first row in the first matrix and the first column in the second matrix. Multiply the first terms, then the second terms, and then the third terms, and so on. Add the products of each multiplication and that is the first term in the product matrix.