Solve Quadratic 1375E9
1. **State the problem:** Solve the quadratic equation $$x^2 - 4x - 12 = 0$$ by factoring.
2. **Recall the factoring method:** To solve by factoring, we express the quadratic in the form $$ax^2 + bx + c = 0$$ and factor it into two binomials $$(x + m)(x + n) = 0$$ where $m$ and $n$ satisfy:
- $m + n = b$
- $m \times n = c$
3. **Identify coefficients:** Here, $a=1$, $b=-4$, and $c=-12$.
4. **Find two numbers that multiply to $-12$ and add to $-4$:**
- Possible pairs: $(6, -2)$, $(-6, 2)$, $(4, -3)$, $(-4, 3)$, etc.
- Check sums:
- $6 + (-2) = 4$ (not $-4$)
- $-6 + 2 = -4$ (correct)
5. **Write the factored form:**
$$x^2 - 4x - 12 = (x - 6)(x + 2) = 0$$
6. **Solve each factor for zero:**
- $x - 6 = 0 \Rightarrow x = 6$
- $x + 2 = 0 \Rightarrow x = -2$
7. **Final answer:**
$$\boxed{x = 6 \text{ or } x = -2}$$