Lesson Objectives: I will be able to … Solve one-step inequalities by using addition Solve one-step inequalities by using subtraction Language Objective: I will be able to … Read, write, and listen about vocabulary, key concepts, and examples

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Example 1: Using Addition and Subtraction to Solve Inequalities Page 7 Solve the inequality d – 5 > -7 and graph the solutions. +5 +5 d + 0 > –2 d > –2 d – 5 > –7 Since 5 is subtracted from d, add 5 to both sides to undo the subtraction. Draw an empty circle at –2. –10 –8 –6 –4 –2 2 4 6 8 10 Shade all numbers greater than –2 and draw an arrow pointing to the right.

Solve the inequality q - 3.5 < 7.5 and graph the solutions. Your Turn 1 Page 7 Solve the inequality q - 3.5 < 7.5 and graph the solutions. q – 3.5 < 7.5 Since 3.5 is subtracted from q, add 3.5 to both sides to undo the subtraction. + 3.5 +3.5 q – 0 < 11 q < 11 –7 –5 –3 –1 1 3 5 7 9 11 13

Since there can be an infinite number of solutions to an inequality, it is not possible to check all the solutions. You can check the endpoint and the direction of the inequality symbol. The solutions of x + 9 < 15 are given by x < 6.

Example 2: Auction Application Page 8 Mrs. Lawrence wants to buy an antique bracelet at an auction. She is willing to bid no more than $550. So far, the highest bid is $475. Write and solve an inequality to determine the amount Mrs. Lawrence can add to the bid. Check your answer. Let x represent the amount Mrs. Lawrence can add to the bid. $475 plus amount can add is at most $550. x + 475 ≤ 550 475 + x ≤ 550 Check the endpoint, 75. Check a number less than 75. –475 – 475 x ≤ 75 0 + x ≤ 75 475 + x = 550 475 + 75 550 550 550  475 + x ≤ 550 475 + 50 ≤ 550 525 ≤ 550  Mrs. Lawrence is willing to add $75 or less to the bid.

Classwork Assignment #2 Holt 3-2 #1 – 6, 14, 22, 26 – 29