3-4-5........OR............ multiply x6

A right triangle measures 3x4x5 ..........

18x24x30

Measure and mark the wall 24 feet from the front corner..........or place a stake at that location

Take a tape and measure out from the front corner of the wall 18 feet and draw a short arc in the dirt.........

Take the tape and measure 30 feet diagonally from the mark/stake along the wall to the arc in the dirt and draw a new arc..........

The intersection of the two arcs is a square line to the wall.....18' from the wall at the approximate location for the support........



For more read about "The 47th Problem of Euclid" and more at:

http://journeytoforever.org/farm_library/device/devices2.html