Main Idea Key Concept Properties of Inequality Example

Main Idea Key Concept: Properties of Inequality Example 1: Solve Inequalities Example 2: Solve Inequalities Key Concept: Properties of Inequality Example 3: Multiply by a Negative Number Example 4: Divide by a Negative Number Example 5: Real-World Example

• Solve and graph one-step inequalities by using the Multiplication or Division Properties of Inequality.

Solve Inequalities Solve 6 x < – 30. Graph the solution set on a number line. 6 x < – 30 Write the inequality. Division Property of Inequality x< – 5 Simplify. Draw an open dot at – 5 with an arrow to the left. Answer:

Solve 21 < 3 n. Graph the solution set on a number line. A. n < 7 B. n > 7 C. n < – 7 D. n > – 7

Solve Inequalities 1 p ≥ 9. Graph the solution set on a Solve __ 2 number line. Write the inequality. Multiplication Property of Inequality Simplify.

Solve Inequalities The solution is p ≥ 18. Graph the solution set. Draw a closed dot at 18 with an arrow to the right. Answer:

k – 2. Graph the solution set on a number Solve __ 6 line. A. k ≤ 12 B. k ≤ – 12 C. k ≥ 12 D. k ≥ – 12

Multiply or Divide by a Negative Number b Solve the inequality __ ≤ 5. Graph the solution set – 4 on a number line. Write the inequality. Multiplication Property of Inequality; reverse inequality symbol Simplify. Answer:

h Solve __ > – 3. Graph the solution set on a number line. – 6 A. h < 18 B. h > 18 C. h < – 18 D. h > – 18

Multiply or Divide by a Negative Number Solve the inequality – 4 n > – 60. Graph the solution set on a number line. Write the inequality. Division Property of Inequality; reverse inequality symbol Simplify. Answer:

Solve – 8 n 72. Graph the solution set on a number line. A. n ≤ – 9 B. n ≥ – 9 C. n ≤ 9 D. n ≥ 9

BOOKS Jesse is filling a box with books that weigh 2 pounds each. The box can hold at most 15 pounds of books. Assuming that space is not an issue, write and solve an inequality to find how many books Jesse can put in the box. The phrase at most means less than or equal to. Let p = the number of books in the box.

Write the inequality. Division Property of Inequality Simplify. Answer: The solution is p ≤ 7. 5. He can put at most 7 books in the box.

MONEY Victor has $13 to buy trail mix for a hiking trip. A pound of trail mix costs $5. Write and solve an inequality to find how many pounds of trail mix Victor can buy. A. 5 x ≤ 13; at most 2. 6 pounds B. 5 x ≥ 13; at least 2. 6 pounds C. 13 x ≤ 5; at most about 0. 4 pound D. 13 x ≥ 5; at least about 0. 4 pound