In this video, we will be learning how to solve inequalities using multiplication or division. After you finish this lesson, view all of our Algebra 1 lessons and practice problems.

## Example of Solving an Inequality Using Multiplication/Division

Divide by -3 on both sides (Don’t forget to flip the inequality sign since we are dividing by a negative!)

Graph the inequality

### Example 1

To solve for , we have to divide both sides by

Then, graph the inqequality

### Example 2

To solve for , let’s multiply both sides by

Then, graph the inqequality

## Video-Lesson Transcript

Let’s go over how to solve inequalities using multiplication or division

The rules are very similar to solving regular equations except for one rule.

If we multiply or divide by a negative number, we have to flip inequality.

Here are some examples:

To solve for , we have to divide both sides by .

Next we have

Let’s solve by dividing both sides by

Since we divide it by a negative number, the inequality sign should be flipped.

Let’s look at another example.

So, we’ll solve by dividing both sides by .

Here, its negative divided by positive.

Remember the rule? If we multiply or divide by a negative number, we have to flip inequality.

In this example, we are dividing by positive . So there’s no need to flip the sign.

So the answer is:

Next, let’s have

To solve for , let’s divide both sides by .

Here, we multiplied by a negative number so we have to flip the inequality sign.

So the answer is

So in solving inequalities using multiplication or division, follow the same rules to solve for .

But if we, at any point, multiply or divide by a negative number, we have to flip the inequality sign.