7.2 Writing Two-Step Inequalities Essential Question: How do you write a two step inequality? Objective: SWBAT write and solve a two step inequality. Inequality Rules CASE STUDY 3x + 5 ≥ 20 -5 -5 Subtract 5 from both sides 3x ≥ 15 /3 /3 Divide both sides by 3 Solution: x ≥ 5 Check: 3(6) + 5 ≥ 20 18 + 5 ≥ 20 23 ≥ 20 True. -2k + 5 ≥ -3 -5 -5 Subtract 5 from both sides -2k ≥ -8 /-2 /-2 Divide both sides by -2 Flip the sign Solution: k ≤ 4 Check: -2(2) + 5 ≥ -3 -4 + 5 ≥ -3 1 ≥ -3 True Example Two A mountain climbing team is camped at an altitude of 18,460 feet on Mount Everest. The team wants to reach the 29,029 foot summit within 6 days. Write an inequality to find the average number of feet per day the team must climb to accomplish its objective. Step 1: What is it that you are trying to find? This will be your variable. Step 2: What is it your problem must equal, be less than, or be greater than? Step 3: Identify important information in the problem you will need. Step 4: Put it all together. Example Three Write a word problem to represent 2x + 20 ≤ 50. Step 1: Analyze what each part of the inequality means mathematically. Step 2: Create a story that matches each operation.