Learn the basics of subtraction with this free lesson, which includes subtraction basics as well as interactives for you to practice.

### Solving Problems

In Introduction to Addition, you learned how to use **counting** to solve addition problems. That skill can also be used to solve subtraction problems.

#### Ways to Count

We're going to take a look at two ways you can use counting to subtract. First we'll count with **objects**.

To count with objects, use the objects to show the first number in the expression.

Let's try it with this expression, 9 - 4.

We'll start by showing the number 9. We'll need 9 objects.

We'll start by showing the number 9. We'll need 9 objects.

We'll start by showing the number 9. We'll need 9 objects.

We'll start by showing the number 9. We'll need 9 objects.

We'll start by showing the number 9. We'll need 9 objects.

We'll start by showing the number 9. We'll need 9 objects.

We'll start by showing the number 9. We'll need 9 objects.

We'll start by showing the number 9. We'll need 9 objects.

We'll start by showing the number 9. We'll need 9 objects.

We'll start by showing the number 9. We'll need 9 objects.

We're subtracting 4, so we'll take away 4 of the objects.

We're subtracting 4, so we'll take away 4 of the objects.

We're subtracting 4, so we'll take away 4 of the objects.

We're subtracting 4, so we'll take away 4 of the objects.

We're subtracting 4, so we'll take away 4 of the objects.

Now we can finish this expression. All we have to do is **count** the remaining objects.

Now we can finish this expression. All we have to do is **count** the remaining objects.

Now we can finish this expression. All we have to do is **count** the remaining objects.

Now we can finish this expression. All we have to do is **count** the remaining objects.

Now we can finish this expression. All we have to do is **count** the remaining objects.

Now we can finish this expression. All we have to do is **count** the remaining objects.

There are 5 objects left, so our answer is **5**.

To finish, we'll write 5 to the right of the equals sign.

#### Try This!

Solve these expressions.

#### Number Lines

Another way to solve subtraction problems is to use a **number line**.

Subtracting with a number line is simple.

When you subtract, you count by moving **left** one number at a time.

When you subtract, you count by moving **left** one number at a time.

When you subtract, you count by moving **left** one number at a time.

Let's practice subtracting with a number line.

We need to start counting from the **first number** in our expression.

Here, that number is 9...

Here, that number is 9...So, we'll start counting at the 9 mark on the number line.

The **second number **in our expression is how much we're subtracting.

Here, that number is 4...

Here, that number is 4...So, we'll move to the left 4 times.

Here, that number is 4...So, we'll move to the left 4 times.

Here, that number is 4...So, we'll move to the left 4 times.

Here, that number is 4...So, we'll move to the left 4 times.

We landed on 5. This means that 9 - 4 = 5.

We'll write 5 to the right of the equals sign. Our expression is complete!