View more at www.MathAndScience.com.
In this lesson, you will learn what factors determine if a parabola (quadratic equation) opens up or down in the xy plane. We will see that the coefficient of the x^2 term determines this behavior.
If this coefficient is positive, the parabola opens upward. If the coefficient if negative, the parabola opens downwards. The magnitude of this number determines how steep the parabola is drawn. We will illustrate these ideas by working example problems and also by using a computer demo.