Sound intensity varies inversely as the square of the distance from the source.
At an outdoor concert, two bands set up 2000 feet from each other. Initially, the Twisted Turtles play at the same volume as Hogroast. Verify that it is least noisy at the midpoint of the line segment between the bands. They turn up their equipment until they are playing twice as loud as the Twisted Turtles. Now find the point on minimal noise on the segments connecting the bands.