1. **State the problem:** Solve the quadratic equation $$w^2 + 12w - 40 = 0$$ and find which of the given options is a solution.
2. **Formula used:** To solve a quadratic equation $$aw^2 + bw + c = 0$$, use the quadratic formula:
$$w = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$$
where $a=1$, $b=12$, and $c=-40$.
3. **Calculate the discriminant:**
$$\Delta = b^2 - 4ac = 12^2 - 4 \times 1 \times (-40) = 144 + 160 = 304$$
4. **Find the roots:**
$$w = \frac{-12 \pm \sqrt{304}}{2}$$
Since $\sqrt{304} = \sqrt{16 \times 19} = 4\sqrt{19}$, we have:
$$w = \frac{-12 \pm 4\sqrt{19}}{2} = -6 \pm 2\sqrt{19}$$
5. **Solutions:**
$$w_1 = -6 + 2\sqrt{19}$$
$$w_2 = -6 - 2\sqrt{19}$$
6. **Check options:**
- Option A: $6 - 2\sqrt{19}$ (not equal to either root)
- Option B: $2\sqrt{19}$ (not equal)
- Option C: $\sqrt{19}$ (not equal)
- Option D: $-6 + 2\sqrt{19}$ (matches $w_1$)
**Final answer:** Option D is a solution to the equation.
Quadratic Solution 922Dda
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