To solve the quadratic equation x² + 12x + 5 = 0 by completing the square, follow these steps:
- Start with the equation:
x² + 12x + 5 = 0
- Move the constant term to the other side of the equation:
x² + 12x = -5
- To complete the square, take half of the coefficient of x (which is 12), square it, and add it to both sides:
Half of 12 is 6, and squaring it gives us 36. Now add 36 to both sides:
x² + 12x + 36 = -5 + 36
- Simplify the equation:
x² + 12x + 36 = 31
- Now, the left side is a perfect square trinomial:
(x + 6)² = 31
- Take the square root of both sides:
x + 6 = ±√31
- Isolate x by subtracting 6 from both sides:
x = -6 ± √31
Therefore, the solutions to the equation x² + 12x + 5 = 0 are:
x = -6 + √31 and x = -6 – √31.