How to Find the zeros when graphing a quadratic equation

In this tutorial the instructor shows how to graph a parabola and also how to find its roots which are also known as zeroes. He gives the quadratic formula of how to find x-intercepts of a parabola. He takes an example and substitutes the values and finds out the values of the roots of the parabola. Now he substitutes these values in the equation to obtain the corresponding y coordinates. Now using these pairs of values he plots the parabola on a graph and draws it. This video shows how to find the zeros or roots of a parabola and how to graph it.