Matrix

The order is the rows and columns

Identity Matrix

Think of it as the number 1

Adding and Subtracting Matrix

Note that the order is the same for each

Multiplication Matrix

The bottom example A(BC) = (AB)C is very circumstantial be careful!!!

Division matrix

Does not exist!!!

Inverse matrix

THE DETERMINANT IS (AD-BC)

MAKE SURE AD-BC ≠ 0