How do you solve x² + 12x + 5 = 0 using the completing the square method?

To solve the quadratic equation x² + 12x + 5 = 0 by completing the square, follow these steps:

  1. Start with the equation:

x² + 12x + 5 = 0

  1. Move the constant term to the other side of the equation:

x² + 12x = -5

  1. 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

  1. Simplify the equation:

x² + 12x + 36 = 31

  1. Now, the left side is a perfect square trinomial:

(x + 6)² = 31

  1. Take the square root of both sides:

x + 6 = ±√31

  1. 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.

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