Quadratic Solution 3Ebd38
1. **State the problem:** Find the value(s) of $x$ when $-2x^2 - 5x + 7 = 0$.
2. **Formula used:** This is a quadratic equation of the form $ax^2 + bx + c = 0$. The solutions are given by the quadratic formula:
$$x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$$
where $a = -2$, $b = -5$, and $c = 7$.
3. **Calculate the discriminant:**
$$\Delta = b^2 - 4ac = (-5)^2 - 4(-2)(7) = 25 + 56 = 81$$
Since $\Delta > 0$, there are two real solutions.
4. **Apply the quadratic formula:**
$$x = \frac{-(-5) \pm \sqrt{81}}{2(-2)} = \frac{5 \pm 9}{-4}$$
5. **Find the two solutions:**
- For $+$ sign:
$$x = \frac{5 + 9}{-4} = \frac{14}{-4} = -3.5$$
- For $-$ sign:
$$x = \frac{5 - 9}{-4} = \frac{-4}{-4} = 1$$
**Final answer:** The values of $x$ are $-3.5$ and $1$.