1. The problem statement, all variables and given/known data Given a parametric eqn for the x,y coordinates , x(t),y(t) , how can i find the control points? 2. Relevant equations de Casteljau's algorithm is used to compute the value for a given t given the control points. 3. The attempt at a solution Control Points 0,3 are given for values t=0,t=1. Maybe for an arbitrary t, you can backstep the de Casteljau algorithm, and end up in a relation of the other two dependent on the first and last control points' coordinates? But i tried this and get no definite solution.