Mathematics for IGCSE & O level - Equations (Section 8 - No. 8)
What form does the quadratic equation take after completing the square?
a(x + p)² + q = 0
ax² + bx + c = 0
(x + p)(x - q) = 0
x = -b ± √(b² - 4ac) / 2a
Explication
Completing the square rewrites the quadratic expression into this form.