To solve the quadratic equation \( x^2 + 14x + 13 = 27 \) by completing the square, we follow these steps:
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Rearrange the equation: Move all terms to one side of the equation:
\[ x^2 + 14x + 13 - 27 = 0 \]
Simplifying gives:
\[ x^2 + 14x - 14 = 0 \]
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Complete the square: We need to manipulate the quadratic expression \( x^2 + 14x \).
To complete the square, 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 expression as follows:
\[ x^2 + 14x + 49 - 49 - 14 = 0 \]
This can be reorganized as:
\[ (x + 7)^2 - 63 = 0 \]
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Solve for \( x \): Now set the equation to zero and solve:
\[ (x + 7)^2 = 63 \]
Taking the square root of both sides gives:
\[ x + 7 = \pm \sqrt{63} \]
Finally, solve for \( x \):
\[ x = -7 \pm \sqrt{63} \]
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Simplify \( \sqrt{63} \): We can simplify \( \sqrt{63} \) to \( 3\sqrt{7} \):
\[ x = -7 \pm 3\sqrt{7} \]
Therefore, the solutions are:
\[ x = -7 + 3\sqrt{7}, \quad x = -7 - 3\sqrt{7} \]
So the correct response is:
x=−7+3√7, −7−3√7