Quadratic Equation Solver

Solve ax² + bx + c = 0 step by step

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About Quadratic Equation Solver

A comprehensive quadratic equation solver that finds roots of ax² + bx + c = 0 using the quadratic formula. Shows discriminant analysis (two real, one repeated, or complex roots), step-by-step working, vertex form conversion, axis of symmetry, and a visual parabola preview. Handles all cases including complex/imaginary roots. Essential for algebra students, engineers, and anyone solving second-degree polynomial equations.

Quadratic Equation Solver Features

  • Quadratic formula
  • Complex roots
  • Discriminant analysis
  • Vertex form
  • Step-by-step
The quadratic equation ax² + bx + c = 0 appears everywhere: physics (projectile motion), engineering (beam deflection), finance (break-even analysis), and computer graphics (ray-sphere intersection). The quadratic formula x = (-b ± √(b²-4ac)) / 2a provides the solution for any coefficients.

How to Use

Enter the coefficients a, b, and c:

  • a: Coefficient of x² (must not be 0)
  • b: Coefficient of x
  • c: Constant term

The Discriminant

The discriminant D = b² - 4ac determines the nature of roots:

  • D > 0: Two distinct real roots
  • D = 0: One repeated real root
  • D < 0: Two complex conjugate roots

Vertex Form

Every quadratic can be written as a(x - h)² + k where (h, k) is the vertex. h = -b/(2a) is the axis of symmetry, and k = c - b²/(4a) is the minimum (or maximum) value.

Step-by-Step Instructions

  1. 1Enter coefficient a (x² term).
  2. 2Enter coefficient b (x term).
  3. 3Enter coefficient c (constant).
  4. 4View the roots and discriminant analysis.
  5. 5Study the step-by-step solution.

Quadratic Equation Solver — Frequently Asked Questions

What if the discriminant is negative?+

The equation has two complex conjugate roots of the form p ± qi, where i = √(-1). These are perfectly valid solutions — they just don't intersect the x-axis on a real number line graph.

Can 'a' be zero?+

No. If a = 0, it becomes a linear equation bx + c = 0 with solution x = -c/b. A quadratic equation requires a ≠ 0 to have an x² term.

What's the relationship between roots and coefficients?+

By Vieta's formulas: the sum of roots = -b/a, and the product of roots = c/a. This is useful for checking your answers or constructing equations from known roots.

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