1. **State the problem:** Solve the inequality $ (x - 4)(x - 2) > 0 $.
2. **Recall the rule:** A product of two factors is positive if both factors are positive or both are negative.
3. **Find critical points:** Set each factor equal to zero:
$$ x - 4 = 0 \Rightarrow x = 4 $$
$$ x - 2 = 0 \Rightarrow x = 2 $$
These points divide the number line into three intervals: $(-\infty, 2)$, $(2, 4)$, and $(4, \infty)$.
4. **Test each interval:**
- For $x < 2$, pick $x=0$:
$$ (0-4)(0-2) = (-4)(-2) = 8 > 0 $$
- For $2 < x < 4$, pick $x=3$:
$$ (3-4)(3-2) = (-1)(1) = -1 < 0 $$
- For $x > 4$, pick $x=5$:
$$ (5-4)(5-2) = (1)(3) = 3 > 0 $$
5. **Write solution:** The inequality holds where the product is positive, so
$$ x \in (-\infty, 2) \cup (4, \infty) $$
6. **Final answer:**
$$ \boxed{x < 2 \text{ or } x > 4} $$
Inequality Solution Ce2B44
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