1. **State the problem:** Solve the inequality $$-4 \leq \frac{3x + 5}{2x - 3}$$ where $$x \in \mathbb{R}$$ and $$x \neq \frac{3}{2}$$ because the denominator cannot be zero.
2. **Recall the rule for inequalities with rational expressions:** When multiplying or dividing by an expression that can be positive or negative, we must consider the sign of the denominator to avoid reversing the inequality incorrectly.
3. **Rewrite the inequality:**
$$-4 \leq \frac{3x + 5}{2x - 3}$$
Multiply both sides by $$2x - 3$$, but consider two cases based on the sign of $$2x - 3$$.
4. **Case 1: $$2x - 3 > 0$$ (i.e., $$x > \frac{3}{2}$$)**
Multiply both sides by $$2x - 3$$ (positive, so inequality direction stays the same):
$$-4(2x - 3) \leq 3x + 5$$
Expand:
$$-8x + 12 \leq 3x + 5$$
Bring all terms to one side:
$$-8x + 12 - 3x - 5 \leq 0$$
$$-11x + 7 \leq 0$$
Add $$11x$$ to both sides:
$$7 \leq 11x$$
Divide both sides by 11 (positive, so inequality stays):
$$\frac{7}{11} \leq x$$
Since $$x > \frac{3}{2}$$ and $$\frac{7}{11} \approx 0.636$$, the solution for this case is:
$$x > \frac{3}{2}$$
5. **Case 2: $$2x - 3 < 0$$ (i.e., $$x < \frac{3}{2}$$)**
Multiply both sides by $$2x - 3$$ (negative, so inequality direction reverses):
$$-4(2x - 3) \geq 3x + 5$$
Expand:
$$-8x + 12 \geq 3x + 5$$
Bring all terms to one side:
$$-8x + 12 - 3x - 5 \geq 0$$
$$-11x + 7 \geq 0$$
Add $$11x$$ to both sides:
$$7 \geq 11x$$
Divide both sides by 11 (positive, inequality stays):
$$\frac{7}{11} \geq x$$
Since $$x < \frac{3}{2}$$ and $$\frac{7}{11} \approx 0.636$$, the solution for this case is:
$$x \leq \frac{7}{11}$$
6. **Combine both cases and consider domain restriction:**
From case 1: $$x > \frac{3}{2}$$
From case 2: $$x \leq \frac{7}{11}$$
7. **Final solution:**
$$x \leq \frac{7}{11}$$ or $$x > \frac{3}{2}$$
This excludes $$x = \frac{3}{2}$$ where the denominator is zero.
**Answer:**
$$\boxed{x \in (-\infty, \frac{7}{11}] \cup (\frac{3}{2}, \infty)}$$
Rational Inequality 6F2975
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