Inequalities
5 minQuiz at the end
Inequality Symbols
| Symbol | Meaning | Example |
|---|---|---|
| > | greater than | x > 5 |
| < | less than | x < 3 |
| β₯ | greater than or equal to | x β₯ 0 |
| β€ | less than or equal to | x β€ 10 |
Solving Inequalities
Solve like an equation, with one important rule:
β οΈ When you multiply or divide by a negative number, flip the inequality sign.
Example: 2x + 3 < 11 β subtract 3: 2x < 8 β divide by 2: x < 4
With a negative: -3x > 9 β divide by -3 and flip: x < -3
Representing on a Number Line
- Open circle (β) β does not include the value: x > 4
- Closed circle (β) β includes the value: x β₯ 4
βββββββββββΊ
4 5 6 (x > 4)
βββββββββββΊ
4 5 6 (x β₯ 4)
Compound Inequalities
Two conditions at once:
- -3 β€ x < 2 means x is between -3 and 2, including -3 but not 2.