Well, you could use the embedded python editor to plot pretty much anything you want, including that graph of x^2+3x-10. You’d have to grid the x values over the range you want and plot vertices at the (x,y,z) positions (x,x^2+3x-10,0) and connect them by a curve or so. You can also make animations that way, for example, if you want to change the coefficients of the equation in time, or if you want to do a camera fly-by of your graph.
Whether this is useful for you depends on your application. You could also try a free matlab-like program called scilab. Hope this helps, feel free to ask more!