Quadratic equations are a fundamental part of algebra and often appear in math homework, tests, and real-world applications. Our Quadratic Equation Solver helps you quickly and accurately find the roots of any quadratic equation. Just input your coefficients (a, b, and c), and instantly discover the equation’s solutions—whether they’re real or complex.
A quadratic equation takes the form ax² + bx + c = 0, where "a" cannot be zero. Quadratic equations can have two solutions, one solution, or no real solutions at all, depending on the discriminant, calculated as D = b² - 4ac.
The calculator uses the quadratic formula:
x = [-b ± √(b² - 4ac)] / (2a)
If the discriminant (D) is positive, you'll get two real solutions. If it's zero, there's one real solution (known as a double root). If negative, the calculator gives you two complex solutions.
Quadratic equations can yield different types of roots:
Use our Quadratic Equation Solver to simplify your math problems and strengthen your algebra skills. Solve equations instantly and gain confidence in your mathematical abilities.
Consider the equation 2x² – 5x – 3 = 0. Plugging the coefficients into the quadratic
formula gives x = [5 ± √(25 + 24)] / 4
. The discriminant is 49, so the square root
equals 7. The two solutions become x = (5 + 7)/4 = 3
and x = (5 – 7)/4 = –0.5
.
Try entering these numbers in the calculator to verify that the vertex lies halfway between the
roots at x = 1.25
with a minimum value of y = –6.125
.
Every quadratic equation corresponds to a parabola. Positive a values open upward like a bowl, while negative values open downward. The vertex marks the maximum or minimum point of the curve, and the axis of symmetry runs through the vertex. Plotting the solutions from the example reveals how the graph crosses the x-axis at the roots. Visualizing the curve helps students connect algebraic solutions to geometric intuition.
The quadratic formula works for every case, yet alternative methods can be faster in specific situations. Factoring the expression is quick when the coefficients yield tidy integer roots. Completing the square shows how the formula arises and is useful when deriving a vertex form for graphing. Some graphing calculators also solve by plotting and locating intercepts. Experiment with different approaches to build flexibility in problem solving.
Quadratic equations appear in physics when analyzing projectile motion, in economics when optimizing profit functions, and in engineering when modelling parabolic antennas. Mastering this topic provides a foundation for advanced studies in calculus, statistics, and science. Whenever you encounter a squared term, the techniques in this solver can guide you toward an exact solution.
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