1. **Problem:** Solve the equation using logarithmic laws: $$\log_4 x + \log_4 (x - 6) = 2$$
2. **Formula and rules:** Recall the logarithmic product rule: $$\log_b A + \log_b B = \log_b (AB)$$
3. **Apply the product rule:**
$$\log_4 x + \log_4 (x - 6) = \log_4 [x(x - 6)] = 2$$
4. **Rewrite the equation:**
$$\log_4 [x(x - 6)] = 2$$
5. **Convert logarithmic form to exponential form:**
$$x(x - 6) = 4^2$$
6. **Calculate the right side:**
$$x^2 - 6x = 16$$
7. **Bring all terms to one side:**
$$x^2 - 6x - 16 = 0$$
8. **Solve the quadratic equation using the quadratic formula:**
$$x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$$ where $$a=1$$, $$b=-6$$, $$c=-16$$
9. **Calculate the discriminant:**
$$\sqrt{(-6)^2 - 4(1)(-16)} = \sqrt{36 + 64} = \sqrt{100} = 10$$
10. **Find the roots:**
$$x = \frac{6 \pm 10}{2}$$
11. **Calculate each root:**
- $$x = \frac{6 + 10}{2} = \frac{16}{2} = 8$$
- $$x = \frac{6 - 10}{2} = \frac{-4}{2} = -2$$
12. **Check for domain restrictions:**
Since $$\log_4 x$$ and $$\log_4 (x - 6)$$ require $$x > 0$$ and $$x - 6 > 0$$, we must have $$x > 6$$.
13. **Discard invalid root:**
$$x = -2$$ is invalid because it is less than 6.
14. **Final answer:**
$$\boxed{8}$$
Logarithmic Equation 3E03F3
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