How to Solve a Quadratic Equation x² + 10x + 24 by Completing the Square

To solve the quadratic equation x² + 10x + 24 = 0 by completing the square, follow these steps:

  1. Move the constant term to the other side:
  2. Start by rearranging the equation:

    x² + 10x = -24

  3. Complete the square:
  4. To complete the square, we need to add the square of half the coefficient of x to both sides of the equation. The coefficient of x is 10, so half of that is 5, and squaring it gives us 25.

    Add 25 to both sides:

    x² + 10x + 25 = 1

  5. Rewrite the left side as a square:
  6. The left side can now be factored as:

    (x + 5)² = 1

  7. Take the square root of both sides:
  8. Now, take the square root of both sides, remembering to consider both the positive and negative roots:

    x + 5 = ±1

  9. Isolate x:
  10. We solve for x by isolating it:

    1. For the positive root: x + 5 = 1
      ightarrow x = 1 – 5
      ightarrow x = -4
    2. For the negative root: x + 5 = -1
      ightarrow x = -1 – 5
      ightarrow x = -6

The solutions to the quadratic equation x² + 10x + 24 = 0 are:

x = -4 and x = -6

Completing the square is a useful technique, especially when you want to find vertex form or solve quadratics that may not be easily factorable using traditional methods.

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