1. **Problem statement:** Solve the equation $$(x - 2)(x - 3) = 20$$ for $x$.
2. **Formula and rules:** To solve this, first expand the left side using the distributive property (FOIL method):
$$ (x - 2)(x - 3) = x^2 - 3x - 2x + 6 = x^2 - 5x + 6 $$
3. **Rewrite the equation:**
$$ x^2 - 5x + 6 = 20 $$
4. **Bring all terms to one side to set the equation to zero:**
$$ x^2 - 5x + 6 - 20 = 0 $$
$$ x^2 - 5x - 14 = 0 $$
5. **Solve the quadratic equation:** Use the quadratic formula:
$$ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} $$
where $a=1$, $b=-5$, and $c=-14$.
6. **Calculate the discriminant:**
$$ \Delta = b^2 - 4ac = (-5)^2 - 4(1)(-14) = 25 + 56 = 81 $$
7. **Find the roots:**
$$ x = \frac{-(-5) \pm \sqrt{81}}{2(1)} = \frac{5 \pm 9}{2} $$
8. **Evaluate each root:**
- For $+$:
$$ x = \frac{5 + 9}{2} = \frac{14}{2} = 7 $$
- For $-$:
$$ x = \frac{5 - 9}{2} = \frac{-4}{2} = -2 $$
9. **Final answer:**
$$ x = 7 \quad \text{or} \quad x = -2 $$
Solve Quadratic Fc20Eb
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