Solve this quadratic equation by completing the square.
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Answer:
C
Step-by-step explanation:
x² + 6x = 18
To complete the square, take the coefficient of the x term, halve it, square the result, then add to both sides.
(6/2)² = 3² = 9
x² + 6x + 9 = 18 + 9
(x + 3)² = 27
x + 3 = ±√27
x = -3 ± √27