Margo and Sven are outside in a field, standing right next to each other and talking. We'll put x,y coordinates on the field and measure everything in meters. Ursula, a friend of both Margo and Sven, is also outside walking due north (positive y-direction) at . When Ursula crosses the origin (at ) Margo and Sven (at coordinates ) notice her and decide to walk over and say hello.
Margo knows a little physics, and so she figures out how she should walk at to meet Ursula in the shortest amount of time. Sven doesn't know any physics, so he just always walks directly towards Ursula, also at , until he catches up to her.
If the time Sven meets Ursula is and the time Margo meets Ursula is , what is in seconds?