The graph of a quadratic equation has the general form: "y(x) = ax²+bx+c". The top of the chart, i.e. the minimum point (or maximum when a<0) is reached when x=-b/(2a). This means that if a>0, the vertex of the graph will be to the left of the y-axis when b>0, and to the right when b<0. And when a<0, then vice versa