The quadratic equations are second-degree equations in x that have maximum two solutions for x. These two solutions for x are also called the roots of the quadratic equations. We shall learn more about the roots of a quadratic equation in the next sub-topic.

A quadratic equation in one variable also called a second-degree polynomial equation in one variable. A second-degree equation in one variable is an equation in which the variable is raised to the second power. For example, 2x² + x - 6 = 0, 3y² = 7y - 4 and 3x² + 13x + 12 = 0 are quadratic equations.

Frequently, quadratic equations occur in nonstandard form but where necessary they can be rearranged into standard form.