Quadratic Equation Calculator

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Created by: James Porter

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Solve quadratic equations in the form ax² + bx + c = 0 with our free calculator. Get instant solutions, including real and complex roots, discriminant analysis, and step-by-step explanations.

What is a Quadratic Equation Calculator?

A quadratic equation calculator is a tool that solves equations in the form ax² + bx + c = 0, where a, b, and c are coefficients and a ≠ 0. These equations are fundamental in algebra and appear in various real-world applications, from physics to engineering.

This calculator helps you find the roots (solutions) of quadratic equations using the quadratic formula. It provides both real and complex solutions, along with a step-by-step explanation of the calculation process.

Quadratic Equation Formulas

The quadratic formula is used to find the solutions of a quadratic equation:

x = (-b ± √(b² - 4ac)) / (2a)

Variables:

  • x: The unknown variable (roots/solutions)
  • a: Coefficient of x² (must not be zero)
  • b: Coefficient of x
  • c: Constant term
  • Δ (Discriminant): b² - 4ac

The discriminant (Δ) determines the nature of the roots:

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

How to Calculate Quadratic Equations: Example

Let's solve the equation: 2x² + 5x - 3 = 0

  1. Identify the coefficients:
    • a = 2
    • b = 5
    • c = -3
  2. Calculate the discriminant:
    Δ = b² - 4ac Δ = 5² - 4(2)(-3) Δ = 25 + 24 Δ = 49
  3. Apply the quadratic formula:
    x = (-5 ± √49) / (2 * 2) x = (-5 ± 7) / 4
  4. Calculate both solutions:
    • x₁ = (-5 + 7) / 4 = 0.5
    • x₂ = (-5 - 7) / 4 = -3

Common Applications

  • Physics: Calculating projectile motion, determining maximum height and range
  • Engineering: Solving problems involving area, volume, and structural analysis
  • Economics: Finding break-even points and profit maximization
  • Architecture: Designing parabolic structures and calculating optimal dimensions
  • Computer Graphics: Implementing collision detection and curve rendering

Sources and References

  1. Stewart, J. (2015). Calculus: Early Transcendentals. Cengage Learning.
  2. Larson, R., & Hostetler, R. P. (2018). College Algebra. Cengage Learning.
  3. National Council of Teachers of Mathematics. (2020). Principles and Standards for School Mathematics.