1. **State the problem:** Solve the equation $3x(x + 1) = -5$ for $x$.
2. **Rewrite the equation:** Expand the left side:
$$3x(x + 1) = 3x^2 + 3x$$
So the equation becomes:
$$3x^2 + 3x = -5$$
3. **Bring all terms to one side:**
$$3x^2 + 3x + 5 = 0$$
4. **Identify coefficients:**
Here, $a = 3$, $b = 3$, and $c = 5$.
5. **Use the quadratic formula:**
$$x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$$
Substitute values:
$$x = \frac{-3 \pm \sqrt{3^2 - 4 \times 3 \times 5}}{2 \times 3} = \frac{-3 \pm \sqrt{9 - 60}}{6} = \frac{-3 \pm \sqrt{-51}}{6}$$
6. **Simplify the discriminant:**
Since $\sqrt{-51} = i\sqrt{51}$ (where $i$ is the imaginary unit), the solutions are complex:
$$x = \frac{-3 \pm i\sqrt{51}}{6}$$
7. **Express final answer:**
$$x = -\frac{3}{6} \pm \frac{i\sqrt{51}}{6} = -\frac{1}{2} \pm \frac{i\sqrt{51}}{6}$$
**Answer:** The solutions are complex conjugates:
$$x = -\frac{1}{2} + \frac{i\sqrt{51}}{6} \quad \text{and} \quad x = -\frac{1}{2} - \frac{i\sqrt{51}}{6}$$
Solve Quadratic 2D3D75
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