Completing the square
Equations and inequalities · Mathematics
Study notes
Q: Solve x^2 + 6x - 7 = 0 by completing the square. Step 1: Move constant: x^2 + 6x = 7. Step 2: Half of 6 is 3; square: 9. Add both sides: x^2 + 6x + 9 = 16. Step 3: Left is (x + 3)^2 = 16. Step 4: x + 3 = ±4, so x = 1 or x = -7.