Final answer:
To solve x² + 6x = 7 by completing the square, move the constant term to the right side and add the square of half of the coefficient of x to both sides. The solution set is {-7, 1}.
Step-by-step explanation:
To solve the equation x² + 6x = 7 by completing the square, follow these steps:
- Move the constant term to the right side of the equation: x² + 6x - 7 = 0
- Take half of the coefficient of x, square it, and add it to both sides of the equation: x² + 6x + (6/2)² = 7 + (6/2)²
- Simplify: x² + 6x + 9 = 7 + 9
- Factor the perfect square trinomial: (x + 3)² = 16
- Take the square root of both sides: x + 3 = ± √16
- Solve for x: x = -3 ± 4
The solution set of the equation x² + 6x = 7 is {-7, 1}. Therefore, the correct answer is option A. {-7, 1}