In this video, we will be learning how to solve inequalities using addition or subtraction. After you finish this lesson, view all of our Algebra 1 lessons and practice problems.
Example of Solving an Inequality with Addition/Subtraction
Subtract 7 from both sides
Graph the inequality
Example 1
Subtract from both sides
Now, graph the inequality
Example 2
Add from both sides
Now, graph the inequality
Video-Lesson Transcript
Let’s go over how to solve inequalities using addition or subtraction.
Solving this is similar to a regular equation except for the inequality sign instead of an equal sign.
For example:
Let’s solve for by subtracting from both sides of the inequality.
Our answer is
We can graph this by drawing a number line then encircle the number then draw a line to the left which represents the numbers less than .
Now, let’s take a look at subtraction.
We have
To solve , let’s just add on both sides.
Now, let’s graph it by drawing a numbe line.
Let’s draw an open circle on and draw a line to the right to represent numbers greater than .
If we change the sign of into , then our answer would be .
Our graph will have a solid circle on instead of an open circle. Then the line is still going to the right to represent numbers greater than .