We can construct the function:
[tex]f(x)=2x[/tex]
Where [tex]f(x)[/tex] or [tex]y[/tex] is ordinate and [tex]x[/tex] is abscissa.
The function actually represents a line. Since it can have linear form.
[tex]f(x)=2x+0[/tex]
Hope this helps.
r3t40