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Absolute Value Inequalities. Algebra. Solving an Absolute-Value Inequalities. 8 7 6 5 4 3 2 1 0 1 2 3 4 5 6 7 8.
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Absolute Value Inequalities Algebra
Solving an Absolute-Value Inequalities 8 7 6 5 4 3 2 1 0 1 2 3 4 5 6 7 8 8 7 6 5 4 3 2 1 0 1 2 3 4 5 6 7 8
Graphing Absolute Value • When an absolute value is greater than the variable you have a disjunction to graph. • When an absolute value is less than the variable you have a conjunction to graph.
Solving an Absolute-Value Inequality Solve | x 4| < 3 x 4 IS POSITIVE x 4 IS NEGATIVE | x 4| 3 | x 4| 3 x 4 3 x 4 3 x 7 x 1 Reverse inequality symbol. The solution is all real numbers greater than 1 and less than 7. This can be written as 1 x 7.
Solving an Absolute-Value Inequality 2x + 1 IS POSITIVE 2x + 1 IS NEGATIVE | 2x 1 | 3 6 | 2x 1 | 3 6 | 2x 1 | 9 | 2x 1 | 9 2x 1 9 2x 1 +9 2x 10 2x 8 x 4 x 5 6 5 4 3 2 1 0 1 2 3 4 5 6 Solve | 2x 1| 3 6 and graph the solution. 2x + 1 IS POSITIVE 2x + 1 IS NEGATIVE | 2x 1 | 3 6 | 2x 1 | 3 6 | 2x 1 | 9 | 2x 1 | 9 2x 1 9 2x 1 +9 2x 10 2x 8 The solution is all real numbers greater than or equal to 4orless than or equal to 5. This can be written as the compound inequality x 5orx 4. x 4 x 5 Reverse inequality symbol. 4. 5
Strange Results True for All Real Numbers, since absolute value is always positive, and therefore greater than any negative. No Solution Ø. Positive numbers are never less than negative numbers.