# Quadratic Graphs

*Completing square graphically*

Here is the graph of y = x^2+bx ( leading coefficient is set to 1 initially
).Use the slider of b to find out how the graph changes with b. Where are the
intercepts and vertex?

Now adjust the value of c from 0 to generate another graph y = x^2+bx+c. Can
you put the second graph just about the x-axis? What kind of expression do
you obtain when the graph touches the axis?