Algebra 2 1.5 /1.6 Inequality Notes Example 1: y 6 3 Name______________________________________ Graph the solution on a number line. The solution set of an inequality can be expressed using set builder notation. For example, the solution set for this problem can be expressed as _______________________________ You Try: 5w 3 4w 9 Graph the solution on a number line. Multiplying or dividing each side of an inequality by a positive number does not change the truth of the inequality. However, multiplying or dividing each side of an inequality by a negative number requires that the order of the inequality be reversed. For example, to reverse replace it with . Example 2: Solve 4.2x 29.4 Graph the solution on a number line. You Try: 9.2 y 23 Graph the solution on a number line. Example 3: 4c 5c 58 6 You Try: 6(4v 3) 2(10v 3) Graph the solution on a number line Graph the solution on a number line. Algebra 2 1.5 /1.6 Inequality Notes Name______________________________________ Example 4: Enrique’s company pays Sam to advertise on Sam’s website. Sam’s website earns $15 per month plus $0.05 every time a visitor clicks on the advertisement. What is the least number of clicks per month that Sam needs in order to earn $50 per month or more? You Try: Rosa’s cell phone plan cost her $50 per month plus $0.25 for each minute she goes beyond her free minutes. How many minutes can she go beyond her free minutes and still pay less than a total of $70? A compound inequality consists of two inequalities joined by the word and or or. To solve a compound inequality you must solve each part of the inequality. The graph of a compound inequality containing and is the intersection of the solution sets of the two inequalities. Example 5: 8 3 y 7 23 Method 1: Method 2: Graph the solution set on a number line. You Try: 10 3 y 2 19 Graph the solution set on a number line. The graph of a compound inequality containing or is the union of the solution sets of the two inequalities. Example 6: k 6 4 or 3k 14 Graph the solution set Algebra 2 1.5 /1.6 Inequality Notes You Try: x 3 2 or x 4 Name______________________________________ Graph the solution on a number line. Example 7: Solve each inequality. Graph the solution set on a number line. a) x 3 b) x 5 You Try: Solve each inequality. Graph the solution set on a number line. a) t 6 b) u 2 Example 8: Solve 6 y 5 13 Graph the solution set on a number line. You Try: Solve 2 x 2 4 Graph the solution set on a number line. You Try: Solve 5z 2 17 Graph the solution set on a number line