Plotting Quadratic equation MATLAB

Hi, I really would like help on plotting a quadratic equation, in the form of ax^2+bx+c

I’ve been told to make a neat graph by “Center x axis around the extrema of the function (at x=-b/(2a)) is that the roots (if existing) are visible

[Hari Krishna Ravuri]

Please refer https://in.mathworks.com/matlabcentral/answers/324257-how-to-plot-a-quadratic-equation

[Saad Arshad]

Thank you