Multiplying Matrices

Scalar multiplication is when you distribute the number outside the matrix to all the numbers inside the brackets.

To multiply matrices, you first need to write a dimension statement. The dimension statement basically states that the columns of the first matrix must match the rows of the other matrix

2x2*2x2

2x2 2x2

The numbers underlined show that the matrices can be multiplied, since the inside numbers are the same.

The bolded numbers become the dimensions of the new matrix. 

More specifically, you would multiply the first number of the first row on the first matrix with the first number of the first column of the second matrix. You then add the products together and that's the first number of the product matrix. You repeat this until all the numbers of both the matrices have been multiplied, giving you your product matrix.