This sketch shows an exaggeration of what would have happened if the record had been run. What should we do to find the proper position for the corner from these two different points?

The answer is to extend cardinal offsets from the end point of each line toward the other point. The intersection of these offsets would be our true corner point as spelled out in the manual,

but we've already placed one temp stake not two. So what move should we make to get from our single temp stake to the proportionate position?