Main Page | See live article | Alphabetical index A quadratic equation is a polynomial equation of degree 2. The generalized form is ax2 + bx + c = 0. For example, 5x2 + 3x + 4 = 0. The numbers 5, 3 and 4 here are called coefficients: 5 is the coefficient of x2 and 3 is the coefficient of x. A quadratic equation with real or complex coefficients has two complex roots (i.e., solutions), although the two roots may be equal. These roots can be computed using the quadratic formula. See also: linear equation, cubic equation, quartic equation, quintic equation, fundamental theorem of algebra This article is from Wikipedia. All text is available under the terms of the GNU Free Documentation License.