1. **State the problem:** Solve the inequality $$2x^2 - 3x - 16 > 5 - 2x$$ for $x$.
2. **Rewrite the inequality:** Move all terms to one side to set the inequality to zero:
$$2x^2 - 3x - 16 - 5 + 2x > 0$$
3. **Simplify the expression:**
$$2x^2 - 3x + 2x - 16 - 5 > 0$$
$$2x^2 - x - 21 > 0$$
4. **Find the roots of the quadratic equation:**
Solve $$2x^2 - x - 21 = 0$$ using the quadratic formula:
$$x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$$
where $a=2$, $b=-1$, and $c=-21$.
5. **Calculate the discriminant:**
$$\Delta = (-1)^2 - 4 \times 2 \times (-21) = 1 + 168 = 169$$
6. **Calculate the roots:**
$$x = \frac{-(-1) \pm \sqrt{169}}{2 \times 2} = \frac{1 \pm 13}{4}$$
7. **Find the two roots:**
$$x_1 = \frac{1 - 13}{4} = \frac{-12}{4} = -3$$
$$x_2 = \frac{1 + 13}{4} = \frac{14}{4} = 3.5$$
8. **Determine the intervals where the inequality holds:**
Since the parabola opens upwards ($a=2 > 0$), the quadratic is greater than zero outside the roots:
$$x < -3 \quad \text{or} \quad x > 3.5$$
**Final answer:**
$$\boxed{x < -3 \text{ or } x > 3.5}$$
Quadratic Inequality 8Ce006
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