Boat Optimization
A boat on the ocean is 50 meters from the nearest point on a straight shoreline; that point is 200 meters from a restaurant on the shore. A woman plans to row the boat straight to a point on the shore and then walk along the shore to the restaurant. If she walks at 3 meters / minute and rows at 2 meters per minute, at which point on the short should she land to minimize the total travel time.
Drag the point B to change where the woman makes landfall. Watch how this affects the total time on the right-hand plot.