Section 3.1: Solving Multi-Step Inequalities
Multi-step inequalities require more than one operation to isolate the variable. The rules are similar to equations, with one key exception:
- When multiplying or dividing both sides of an inequality by a negative number, reverse the inequality symbol.
Example 1
Solve \( 3x + 5 < 11 \)
Step 1: Subtract 5 from both sides: \( 3x < 6 \)
Step 2: Divide by 3: \( x < 2 \)
Solution: \( x < 2 \)
Example 2 (Negative Coefficient)
Solve \( -2x + 4 \ge 10 \)
Step 1: Subtract 4 from both sides: \( -2x \ge 6 \)
Step 2: Divide by -2 and reverse inequality: \( x \le -3 \)
Solution: \( x \le -3 \)
Practice Problems
- Solve: \( 5x - 7 < 18 \)
- Solve: \( 4x + 9 \ge 1 \)
- Solve: \( -3x + 2 < 8 \)
- Solve: \( 2 - 5x > 12 \)
- Solve: \( -4x - 6 \le 10 \)