What Is Vertex Form?

torley/CC-BY-SA 2.0

The vertex form of a quadratic equation is written like f (x) = a(x – h)2 + k, with the letter h and the letter k being the vertex point of the parabola. It can be used to create an equation when the vertex of the parabola is known, but other points are not.

Quadratic equations are most commonly listed in a quadratic form. They are listed with f (x) = ax^2 + bx +c being the base type of equation. These equations can easily be converted to vertex form by taking a few key steps. The x^2 and the x terms need to be isolated in order to complete the square. The leading coefficient should be factored out and the perfect square trinomial will be complete. The perfect square trinomial can then be simplified and added to one side of the equation. The y term should then be isolated alone on the left side of the problem, leaving the rest of the numbers and coefficients on the right side of the problem. When everything is simplified on the right side of the problem, the equation will then be listed in vertex form. This form will allow the problem solver to find the vertex point of the parabola.