Graph inequalities on number lines
An inequality shows that two values are not equal. Graphing them on a number line is a great way to see all the possible numbers that can be a solution. It's a visual map of all the right answers!
Do this: Read the concept below, then try the quiz or activity.
Lesson 150 of 215
Concept
An inequality compares two values, showing if one is less than (<), greater than (>), less than or equal to (≤), or greater than or equal to (≥). Graphing them helps visualize all the possible solutions.
The Two Types of Circles
1. Open Circle (○):
* Used for "less than" (<) and "greater than" (>).
* It means the number itself is not included in the solution.
2. Closed Circle (●):
* Used for "less than or equal to" (≤) and "greater than or equal to" (≥).
* It means the number itself is included in the solution.Graphing the Four Basic Inequalities
1. x > 3: "x is greater than 3"
* Draw an open circle on 3 (because 3 is not greater than 3).
* Draw an arrow to the right, because all numbers to the right (4, 5, 6...) are greater than 3.
<--|---|---|---⚪---->
1 2 3 42. x < 3: "x is less than 3"
* Draw an open circle on 3.
* Draw an arrow to the left, because all numbers to the left (2, 1, 0...) are less than 3.
<----⚪---|---|---|--->
2 3 4 53. x ≥ 3: "x is greater than or equal to 3"
* Draw a closed circle on 3 (because 3 is equal to 3).
* Draw an arrow to the right.
<--|---|---|---⚫---->
1 2 3 44. x ≤ 3: "x is less than or equal to 3"
* Draw a closed circle on 3.
* Draw an arrow to the left.
<----⚫---|---|---|--->
2 3 4 5Key Idea: The inequality symbol points in the same direction that your arrow should go on the number line!
Try it
Practice: Graph inequalities on number lines.