In mathematics, a **quadratic equation** is a univariate polynomial equation of the second degree. A general quadratic equation can be written in the form

where *x* represents a variable or an unknown, and *a*, *b*, and *c* are constants with *a* ≠ 0. (If *a* = 0, the equation is a linear equation.)

The constants *a*, *b*, and *c* are called respectively, the quadratic coefficient, the linear coefficient and the constant term or free term. The term "quadratic" comes from *quadratus*, which is the Latin word for "square". Quadratic equations can be solved by factoring, completing the square, graphing, Newton's method, and using the **quadratic formula** (given below).

Read more about Quadratic Equation: Quadratic Formula, History, Generalization of Quadratic Equation

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