1. **Problem 1: Solve the rational inequality**
Given: $$\frac{x+2}{x-4} \leq 3$$
2. **Rewrite the inequality:**
Bring all terms to one side:
$$\frac{x+2}{x-4} - 3 \leq 0$$
3. **Find a common denominator and combine:**
$$\frac{x+2}{x-4} - \frac{3(x-4)}{x-4} \leq 0$$
$$\frac{x+2 - 3(x-4)}{x-4} \leq 0$$
4. **Simplify the numerator:**
$$x + 2 - 3x + 12 = -2x + 14$$
So inequality becomes:
$$\frac{-2x + 14}{x-4} \leq 0$$
5. **Factor numerator:**
$$\frac{-2(x - 7)}{x-4} \leq 0$$
6. **Determine critical points:**
Numerator zero at $$x=7$$
Denominator zero at $$x=4$$ (excluded from domain)
7. **Test intervals around critical points:**
Intervals: $$(-\infty,4), (4,7), (7,\infty)$$
- For $$x=0$$ in $$(-\infty,4)$$:
$$\frac{-2(0-7)}{0-4} = \frac{-2(-7)}{-4} = \frac{14}{-4} = -3.5 \leq 0$$ True
- For $$x=5$$ in $$(4,7)$$:
$$\frac{-2(5-7)}{5-4} = \frac{-2(-2)}{1} = 4 > 0$$ False
- For $$x=8$$ in $$(7,\infty)$$:
$$\frac{-2(8-7)}{8-4} = \frac{-2(1)}{4} = -\frac{1}{2} \leq 0$$ True
8. **Check inclusion of critical points:**
At $$x=7$$ numerator zero, fraction zero, so include $$x=7$$.
At $$x=4$$ denominator zero, undefined, exclude $$x=4$$.
9. **Solution:**
$$(-\infty,4) \cup [7,\infty)$$
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10. **Problem 2: Analyze the reciprocal function**
Given: $$f(x) = \frac{1}{3x + 9}$$
**a) Find vertical and horizontal asymptotes:**
- Vertical asymptote where denominator zero:
$$3x + 9 = 0 \Rightarrow x = -3$$
- Horizontal asymptote as $$x \to \pm \infty$$:
Since numerator is constant and denominator grows large, horizontal asymptote is:
$$y = 0$$
**b) Find intercepts:**
- x-intercept: set $$f(x) = 0$$
$$\frac{1}{3x + 9} = 0$$
No solution since numerator 1 never zero, so no x-intercept.
- y-intercept: evaluate at $$x=0$$
$$f(0) = \frac{1}{3(0) + 9} = \frac{1}{9}$$
So y-intercept is $$\left(0, \frac{1}{9}\right)$$
**c) Sketch description:**
- Vertical asymptote at $$x = -3$$
- Horizontal asymptote at $$y = 0$$
- No x-intercept
- y-intercept at $$\left(0, \frac{1}{9}\right)$$
- Graph is a hyperbola with branches in top-left and bottom-right relative to vertical asymptote.
**Final answers:**
- Rational inequality solution: $$(-\infty,4) \cup [7,\infty)$$
- Vertical asymptote: $$x = -3$$
- Horizontal asymptote: $$y = 0$$
- x-intercept: none
- y-intercept: $$\left(0, \frac{1}{9}\right)$$
Rational Inequality Reciprocal
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