Solve Multi-Step Inequalities

Algebra-1

1. Fundamental Concepts

  • Definition: Multi-step inequalities involve solving inequalities that require more than one step to isolate the variable.
  • Operations: Include addition, subtraction, multiplication, and division of both sides by positive or negative numbers.
  • Sign Reversal: Multiplying or dividing both sides of an inequality by a negative number reverses the inequality sign.

2. Key Concepts

Basic Rule:
Distributive Property:
Application: Used in real-world scenarios such as budgeting, physics, and engineering problems.

3. Examples

Example 1 (Basic)

Problem: Solve

Step-by-Step Solution:

  1. Subtract 4 from both sides:
  2. Divide both sides by 3:
Validation: Substitute x=3 → Original: 3(3) + 4 = 13 > 10 ✓

Example 2 (Intermediate)

Problem: Solve

Step-by-Step Solution:

  1. Distribute the 2:
  2. Simplify:
  3. Add 2 to both sides:
  4. Divide both sides by 2:
Validation: Substitute x=3 → Original: 2(3 - 3) + 4 = 4 < 6 ✓

4. Problem-Solving Techniques

  • Isolation Strategy: Always start by isolating the variable on one side of the inequality.
  • Sign Awareness: Be cautious when multiplying or dividing by negative numbers, as it changes the direction of the inequality.
  • Verification Step: After solving, substitute a value from the solution set back into the original inequality to verify correctness.