question: Find the parametric equation of the line through the points (0,.5,1) and (2,1,-3)

work:r=r_0+tvthe vector parallel to the line is <2-0,1-.5,-3-1> I thought I would take (0,.5,1) to be ther_0but the text book didn't. How do I know which initial point to use?

Am I doing this right? I mean is it necessary to find the vector equation and then from that take the parametric equation or is there a faster way?