Quadratic Equation Solver
Free online quadratic equation solver. No sign-up, no installation. Runs entirely in your browser.
Input Coefficients
What is a Quadratic Equation?
A quadratic equation is a polynomial equation of the second degree, written in the standard form ax² + bx + c = 0, where a, b, and c are constants and a ≠ 0.
Quadratic equations appear in many real-world applications including physics (projectile motion), engineering, economics, and geometry. Solutions to these equations are called roots or zeros.
How to Use This Solver
- Enter the coefficients: Input values for a, b, and c in the input fields above.
- Click Solve: Press the “Solve Equation” button to calculate the roots and analysis.
- Review the solution: The tool displays the discriminant, root type, vertex coordinates, exact roots, and step-by-step working.
- View the graph: A visual representation of the parabola is drawn with roots marked on the x-axis.
- Copy results: Click on any output section to copy to clipboard.
Common Use Cases
- Physics: Solving projectile motion problems and calculating trajectory paths.
- Engineering: Designing parabolic structures, antennas, and reflectors.
- Finance: Modeling profit/loss functions and break-even analysis.
- Education: Learning algebra and understanding quadratic functions in high school mathematics.
- Optimization: Finding minimum or maximum values in various applications.
Frequently Asked Questions
What is the discriminant?
The discriminant (Δ) is b² – 4ac. It determines the nature of the roots: if Δ > 0, there are two distinct real roots; if Δ = 0, there is one repeated real root; if Δ < 0, there are two complex conjugate roots.
What is the quadratic formula?
The quadratic formula is x = (-b ± √Δ) / (2a), where Δ = b² – 4ac. This formula always gives the exact solutions to any quadratic equation.
What is the vertex of a parabola?
The vertex is the highest or lowest point on the parabola. For a quadratic function f(x) = ax² + bx + c, the vertex is at h = -b/(2a) and k = f(h).
Can this solver handle complex roots?
Yes! When the discriminant is negative, the roots are complex numbers in the form a + bi. The solver displays both the real and imaginary parts clearly.
What is the axis of symmetry?
The axis of symmetry is a vertical line that divides the parabola into two mirror images. Its equation is x = -b/(2a), which is the same as the x-coordinate of the vertex.
Why must coefficient a be non-zero?
If a = 0, the equation becomes bx + c = 0, which is linear, not quadratic. The quadratic formula and discriminant are only valid when the highest degree term (x²) has a non-zero coefficient.
