# Adding and subtracting matrices

### Adding and subtracting matrices

In this lesson, we will learn how to add and subtract matrices. We can only add or subtract matrices if their dimensions are the same. To add matrices, we simply add the corresponding matrix elements together. To subtract matrices, we simply subtract the corresponding matrix elements together. Not only can we add and subtract matrices, but we can solve matrix equations as well. For example, we can add or subtract both sides of the matrix equations to find out what the variable is.
Basic concepts: Notation of matrices,

#### Lessons

We can add and subtract matrices only if the dimensions of the matrices are the same. For example,

Let

We want to find out what A+B is. We see that we are allowed to add A and B together because both A and B has a dimension of 2 x 3.

To add the two matrices together, we simply just need to add the corresponding matrix elements of A and B. So,

Same idea goes for subtracting. We can subtract them because the dimensions are the same. If we want to find out what A - B is, then

• 1.
Adding and subtracting matrices overview

• 2.
Understanding how to add and subtract matrices
Can we add or subtract the following matrices?
a)

b)

c)

• 3.
Adding matrices
Add the following matrices:
a)

b)

c)

• 4.
Subtracting matrices
Subtract the following matrices
a)

b)

c)

• 5.
Solving matrix equations
Solve the following matrix equations:
a)

b)

c)