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How to Calculate Completing the Square Solver

What is Completing the Square Solver?

Completing the square is an algebraic technique that converts a quadratic expression into perfect square form. It's used to solve quadratics and rewrite parabola equations in vertex form.

Formula

ax² + bx + c = a(x + b/2a)² + (c - b²/4a)

Step-by-Step Guide

  1. 1Identify coefficients a, b, c
  2. 2Move constant to the right side
  3. 3Add (b/2a)² to both sides to complete the square

Worked Examples

Input
x² + 6x + 5 = 0
Result
(x + 3)² = 4 → x = -1 or x = -5
Completing the square yields vertex form

Common Mistakes to Avoid

  • Forgetting the a coefficient when factoring out
  • Adding wrong value to complete the square

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