Solve the equation for all values of x by completing the square. Express your answer in simplest form.

x, squared, plus, 35, equals, 14, x
x
2
+35=
14x

1 answer

To solve the equation \( x^2 + 35 = 14x \) by completing the square, here are the steps:

  1. Rearrange the equation: Move all terms to one side of the equation:

    \[ x^2 - 14x + 35 = 0 \]

  2. Complete the square: To do this, focus on the \( x^2 - 14x \) part.

    • Take half of the coefficient of \( x \) (which is \(-14\)), square it, and add it to both sides. Half of \(-14\) is \(-7\), and squaring it gives \(49\).

    • Therefore, we rewrite the equation as follows:

    \[ x^2 - 14x + 49 - 49 + 35 = 0 \]

    Simplifying this gives:

    \[ (x - 7)^2 - 14 = 0 \]

  3. Solve for \( x \): Add \( 14 \) to both sides:

    \[ (x - 7)^2 = 14 \]

    Now, take the square root of both sides:

    \[ x - 7 = \pm \sqrt{14} \]

    Thus, we can solve for \( x \):

    \[ x = 7 \pm \sqrt{14} \]

  4. Final solution:

    The solutions for \( x \) in simplified form are:

    \[ x = 7 + \sqrt{14} \quad \text{and} \quad x = 7 - \sqrt{14} \]

These are the values of \( x \) that satisfy the original equation.