1. We are asked to solve the quadratic equation $x^2 + 12x - 8 = 0$ using the quadratic formula.
2. The quadratic formula is given by:
$$x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$$
where $a$, $b$, and $c$ are coefficients from the quadratic equation $ax^2 + bx + c = 0$.
3. For the equation $x^2 + 12x - 8 = 0$, we identify $a=1$, $b=12$, and $c=-8$.
4. Calculate the discriminant:
$$\Delta = b^2 - 4ac = 12^2 - 4 \times 1 \times (-8) = 144 + 32 = 176$$
5. Substitute into the quadratic formula:
$$x = \frac{-12 \pm \sqrt{176}}{2 \times 1} = \frac{-12 \pm \sqrt{176}}{2}$$
6. Simplify $\sqrt{176}$:
$$\sqrt{176} = \sqrt{16 \times 11} = 4\sqrt{11}$$
7. So,
$$x = \frac{-12 \pm 4\sqrt{11}}{2}$$
8. Simplify the fraction by dividing numerator and denominator by 2:
$$x = \frac{\cancel{-12} \pm \cancel{4}\sqrt{11}}{\cancel{2}} = -6 \pm 2\sqrt{11}$$
9. Final solutions:
$$x_1 = -6 + 2\sqrt{11}$$
$$x_2 = -6 - 2\sqrt{11}$$
Quadratic Solve 8Eb490
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