Draw a plot - curves

Hi,

I want to draw following figures, but I totally don't know how to do it:

(1) https://mathcurve.com/surfaces.gb/cassini/cassini.shtml

(2) https://mathcurve.com/courbes3d.gb/parabolegauche/parabolegauche.shtml

(3) https://mathcurve.com/courbes2d.gb/biquartic/biquartic.shtml

Could you please write down full MatLab commands. Please help me.

[Rik]

Here is a full Matlab command for you:

fprintf('What did you try yourself?\n')

What did you try yourself?

Have a read here and here. It will greatly improve your chances of getting an answer.