Battle of the Iron Triangle Battle of the Iron Triangle The Battle of the Iron Triangle took place from 16 May to 20 November 1974, when the People's Army of Vietnam (PAVN) 9th Division captured Rach Bap and An Dien The Army of the Republic of Vietnam (ARVN) regained the lost towns in a series of costly counterattacks. The Iron Triangle was an important strategic location, bounded on the north by the jungle and overgrown rubber plantations of the Long Nguyen Secret Zone, on the west by the Saigon River and on the east by the smaller but unfordable obstacle of the Thi Thinh River.
Triangle center honor of Clark Kimberling who created the online encyclopedia of more than 9000 triangle centers, the triangle centers listed in the encyclopedia are collectively called "Kimberling centers". A triangle center P is called a "polynomial triangle center" if the trilinear coordinates of P can be expressed as polynomials in "a", "b" and "c". A triangle center P is called a "regular triangle point" if the trilinear coordinates of P can be expressed as polynomials in Δ, "a", "b" and "c", where Δ is the area of the triangle. A triangle center P is said to be a "major triangle center"