LESSON 8 4 Solving TwoStep Inequalities How do

LESSON 8. 4 Solving Two-Step Inequalities How do you solve a two-step inequality?

ADDITIONAL EXAMPLE 1 Use algebra tiles to model and solve 5 f + 11 ≤ − 4. f ≤ − 3

ADDITIONAL EXAMPLE 2 Ed wants to bicycle at least 75 miles this week. The inequality 11 + 4 b ≥ 75 can be used to find b, the average number of miles he should bike on his remaining 4 bike rides this week. Solve the inequality, and graph the solution set on a number line. b ≥ 16

ADDITIONAL EXAMPLE 3 Dianna is buying lunch for herself and two friends. She has a coupon for $15 off the total bill and wants to spend less than $49 after using the coupon. The equation 3 m − 15 < 49 can be used to find m, the average price of each friend’s lunch. Determine which, if any, of the following values make the equation true: m = 21; m = 22; m = 23. m = 21

8. 4 LESSON QUIZ 7. 10. A, 7. 11. B 1. Solve − 10 ≤ 11. x ≤ 63 2. Solve 52 > − 12 + 8 d. d < 8 3. Solve − 16 p + 111 ≥ − 65. p ≤ 11 4. Charlene is a writer who is going on a trip. She has brought several copies of her latest book in her suitcase. The suitcase itself weighs 5 pounds, and each book weighs 3 pounds. If her full suitcase can weigh no more than 50 pounds, how many books can she bring? at most 15 books

5. Carl is having a party. He has bought 24 brownies and is making 6 more batches of brownies. The inequality 24 + 6 b ≥ 138 can be used to determine how many brownies, b, must be in each batch so that all 138 guests get at least 1 brownie. Determine which of the given values, if any, make the inequality true: b = 20 10; b = 15; b = 20.

How do you solve a two-step inequality? Sample answer: Isolate the variable by performing the same operation on both sides of the inequality. If you divide both sides of the inequality by a negative number, reverse the inequality sign.