To solve the quadratic equation \( x^2 - 6x - 11 = 0 \), we can use the quadratic formula:
\[ x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} \]
In this equation, the coefficients are:
- \( a = 1 \)
- \( b = -6 \)
- \( c = -11 \)
Now, let's plug these values into the quadratic formula.
Calculate the discriminant \( b^2 - 4ac \): \[ b^2 - 4ac = (-6)^2 - 4 \cdot 1 \cdot (-11) = 36 + 44 = 80 \]
Now apply the quadratic formula: \[ x = \frac{-(-6) \pm \sqrt{80}}{2 \cdot 1} = \frac{6 \pm \sqrt{80}}{2} \]
Simplify \( \sqrt{80} \): \[ \sqrt{80} = \sqrt{16 \cdot 5} = 4\sqrt{5} \]
Substitute back into the formula: \[ x = \frac{6 \pm 4\sqrt{5}}{2} \]
Simplify further: \[ x = 3 \pm 2\sqrt{5} \]
Thus, the solutions to the equation \( x^2 - 6x - 11 = 0 \) are: \[ x = 3 + 2\sqrt{5} \quad \text{and} \quad x = 3 - 2\sqrt{5} \]