1. **State the problem:** Solve the quadratic equation $$-4x^2 - x + 4 = 0$$ and find the greatest solution.
2. **Recall the quadratic formula:** For an equation $$ax^2 + bx + c = 0$$, the solutions are given by
$$x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$$
where $a = -4$, $b = -1$, and $c = 4$.
3. **Calculate the discriminant:**
$$b^2 - 4ac = (-1)^2 - 4(-4)(4) = 1 + 64 = 65$$
4. **Apply the quadratic formula:**
$$x = \frac{-(-1) \pm \sqrt{65}}{2(-4)} = \frac{1 \pm \sqrt{65}}{-8}$$
5. **Simplify the expression:**
$$x = \frac{1 \pm \sqrt{65}}{-8} = -\frac{1 \pm \sqrt{65}}{8}$$
6. **Write the two solutions explicitly:**
$$x_1 = -\frac{1}{8} + \frac{\sqrt{65}}{8}$$
$$x_2 = -\frac{1}{8} - \frac{\sqrt{65}}{8}$$
7. **Identify the greatest solution:** Since $\sqrt{65} > 0$, the greatest solution is
$$x_1 = -\frac{1}{8} + \frac{\sqrt{65}}{8}$$
**Final answer:** The greatest solution is option c. $-\frac{1}{8} + \frac{\sqrt{65}}{8}$.
Quadratic Greatest Solution 3C5E88
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