Quadratic Equation Calculator

Solve quadratic equations of the form ax² + bx + c = 0

ax² + bx + c = 0

About Quadratic Equations

A quadratic equation is a polynomial equation of degree 2, written in the standard form ax² + bx + c = 0, where a ≠ 0. The solutions are called roots and can be found using the quadratic formula.

Quadratic Formula

x = (-b ± √(b² - 4ac)) / (2a)

Where the discriminant Δ = b² - 4ac determines the nature of the roots:

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

Key Properties

  • Vertex: The turning point of the parabola at (-b/2a, f(-b/2a))
  • Axis of Symmetry: The vertical line x = -b/2a
  • Y-intercept: The point where the parabola crosses the y-axis at (0, c)
  • Direction: Opens upward if a > 0, downward if a < 0

Examples

Example 1

x² - 5x + 6 = 0

a = 1, b = -5, c = 6

Roots: x = 2, x = 3

Example 2

x² - 4x + 4 = 0

a = 1, b = -4, c = 4

Root: x = 2 (repeated)

Example 3

x² + x + 1 = 0

a = 1, b = 1, c = 1

Complex roots