The vertex form of a quadratic equation is a way of writing out the equation of a parabola. It is written as y = a(x - h)^2 + k, where (h, k) is the vertex of the parabola, and x = h is the axis of symmetry. The vertex form is useful because it provides a significant amount of important information about the parabola with a single glance. Each letter in the equation tells us a different piece of information about the parabola:

• a: The "a" value tells us the direction of the parabolas opening. If a > 0, the parabola opens upwards, and if a < 0, the parabola opens downwards.
• h: The "h" value represents a horizontal shift, which tells us how far left or right the graph has shifted from x = 0.
• k: The "k" value represents a vertical shift, which tells us how far up or down the graph has shifted from y = 0.

To convert a quadratic equation from standard form to vertex form, we can use the process of completing the square. To convert from vertex form to standard form, we can simply multiply out the vertex form.