Question

Solve this quadratic equation by completing the square.

Answer 1

C

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