Learn about quadratic equations and functions with detailed explanations and practice problems on Khan Academy.

To be quadratic, the highest power of any term must be 2 (the x is squared). If there is no equals sign, but it has a quadratic term, then it is a quadratic expression.

Graphing quadratic functions Learn Graphing quadratics: vertex form Graphing quadratics in factored form

We've seen linear and exponential functions, and now we're ready for quadratic functions. We'll explore how these functions and the parabolas they produce can be used to solve real-world …

Want to know the path a soccer ball will take through the air? We need quadratic equations. Some equation-solving strategies, like taking the square root or factoring, work best with friendly …

Solve real-world word problems that involve quadratic models. In this exercise, that models are given in standard form.

Solve quadratic equations using the quadratic formula. For example, solve -9x+10x²+8=14.

Identify the form of a quadratic function that immediately reveals a given feature of that function. Features in question are the y-intercept of the graph, the zeroes ("roots") of the function, and …

Simple quadratic equations like x^2=4 can be solved by taking the square root. This article reviews several examples and gives you a chance to practice on your own.

The quadratic formula allows us to solve any quadratic equation that's in the form ax^2 + bx + c = 0. This article reviews how to apply the formula.