Algebra/Compound and Absolute Value Inequalities

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Compound Inequalities are two inequalities presented as one problem. The variable being solved for may need to only fulfill only one of the inequalities, or both, depending on if the word "and" or "or" is used. There may be many correct answers, or even none at all.

Example: 2x - 9 > 15 or 15 / x < 30

• 2x > 24 or 15 > 30 * x
• x > 12 or x < 1/2

The answer can then be graphed on a number line.

One way to write a compound inequality is with absolute value.

Example - convert |6x + 18| - 3³ > 12 into a compound inequality.

• |6x + 18| > 39
• 6x + 18 > 39 or 6x + 18 < -39