Question 7324
great job on both typing formulas in our formula system as well as getting to the solution. You are almost there.

{{{(x-1)^2+y^2 = 1}}}

that's an equation of a circle with center in point x=1, y=0. 

so, assuming that this is what you want, {{{system( x=1+ cos( phi ), y=sin( phi ) ) }}}.