I hope someone can get to this one fast. Im having trouble trying to plot a surface, z=x^2+y^2+cxy. I know how to plot it using the normal Plot3D but what I want is an ImplicitPlot3D and since im new to mathematica I cant figure out how to get it to do this. I dont want to have to use parametric plotting to do this either. From what I do know, this is probably blasphemy and im sorry I have to say it, but in Maple you can plot the kind of function im looking for by using:
In the equation I am playing with c is a changing variable, and what I am looking for are the transitional values where the surface changes from one quadratic surface to another.