1. **State the problem:** Solve the quadratic equation $x^2 + x - 12 = 0$ and analyze its graph.
2. **Recall the quadratic formula:** For $ax^2 + bx + c = 0$, the solutions are given by
$$x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$$
where $a=1$, $b=1$, and $c=-12$.
3. **Calculate the discriminant:**
$$\Delta = b^2 - 4ac = 1^2 - 4 \times 1 \times (-12) = 1 + 48 = 49$$
4. **Find the roots:**
$$x = \frac{-1 \pm \sqrt{49}}{2 \times 1} = \frac{-1 \pm 7}{2}$$
5. **Evaluate each root:**
- For $+$ sign:
$$x_1 = \frac{-1 + 7}{2} = \frac{6}{2} = 3$$
- For $-$ sign:
$$x_2 = \frac{-1 - 7}{2} = \frac{-8}{2} = -4$$
6. **Find the vertex:** The vertex $x$-coordinate is given by
$$x_v = -\frac{b}{2a} = -\frac{1}{2 \times 1} = -0.5$$
7. **Calculate the vertex $y$-coordinate:**
$$y_v = (x_v)^2 + x_v - 12 = (-0.5)^2 + (-0.5) - 12 = 0.25 - 0.5 - 12 = -12.25$$
8. **Axis of symmetry:** The vertical line through the vertex is
$$x = -0.5$$
9. **Summary:**
- Roots: $x_1 = 3$, $x_2 = -4$
- Vertex: $(-0.5, -12.25)$
- Axis of symmetry: $x = -0.5$
- The parabola opens upwards because $a=1 > 0$.
Final answer: The solutions to the equation are $x=3$ and $x=-4$, with vertex at $(-0.5, -12.25)$ and axis of symmetry $x=-0.5$.
Quadratic Equation 4A498F
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