define 'abstract' class curve to use whith another curve
define message to say about numbers of 'entraces' in graph
create method to return string of equation.
create new class of equation to trait polar coordinates
define @current to trait current equation (could be cartesian or polar coordinates)
define new method to change propietes of polar coordinates (receive a symbol whit :up, :down, :left or :right to change position of cicloide).
read buttons to change values in cicloide. show equation on scree.