I've obtained a trend line from a particular set of data. What I'd like to do now is to reuse this trend line to predict values from a given pair (x,y) of coordinates.

To put it another way, I have one pair (x,y) that I know is correct for sure. I don't know any other point. Let's assume the behavior of this new set is similar to the one I've got the trend line from. Is there any way Excel could compute other points following this trend line?