1. **State the problem:** Solve the quadratic equation $$2x(x + 4) = -3x^2 - 2x + 40$$ for $x$.
2. **Rewrite the equation:** Expand the left side:
$$2x(x + 4) = 2x^2 + 8x$$
So the equation becomes:
$$2x^2 + 8x = -3x^2 - 2x + 40$$
3. **Bring all terms to one side:** Add $3x^2 + 2x - 40$ to both sides:
$$2x^2 + 8x + 3x^2 + 2x - 40 = 0$$
Simplify:
$$5x^2 + 10x - 40 = 0$$
4. **Simplify the equation:** Divide all terms by 5:
$$x^2 + 2x - 8 = 0$$
5. **Use the quadratic formula:** For $ax^2 + bx + c = 0$, solutions are:
$$x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$$
Here, $a=1$, $b=2$, $c=-8$.
6. **Calculate the discriminant:**
$$\Delta = b^2 - 4ac = 2^2 - 4(1)(-8) = 4 + 32 = 36$$
7. **Find the roots:**
$$x = \frac{-2 \pm \sqrt{36}}{2} = \frac{-2 \pm 6}{2}$$
8. **Calculate each root:**
- $$x_1 = \frac{-2 + 6}{2} = \frac{4}{2} = 2$$
- $$x_2 = \frac{-2 - 6}{2} = \frac{-8}{2} = -4$$
**Final answer:** The solutions to the quadratic equation are $$x = 2$$ and $$x = -4$$.
Quadratic Intersection
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