Iron Triangle (Vietnam) Iron Triangle (Vietnam) The Iron Triangle (Vietnamese:"Tam Giác Sắt") was a area in the Bình Dương Province of Vietnam, so named due to it being a stronghold of Viet Minh activity during the war. The region was under control of the Viet Minh throughout the French war in Vietnam and continued to be so throughout the phase of American involvement in the Vietnam War, despite concerted efforts on the part of US and South Vietnamese forces to destabilize the region as a power base for their enemy, the communist North Vietnamese–sponsored and–directed South Vietnamese insurgent movement, the National Liberation Front
Integer triangle then all the other points are at ("x, y") where "x" and "y" range over all positive and negative integers. A lattice triangle is any triangle drawn within a 2D lattice such that all vertices lie on lattice points. By Pick's theorem a lattice triangle has a rational area that either is an integer or has a denominator of 2. If the lattice triangle has integer sides then it is Heronian with integer area. Furthermore, it has been proved that all Heronian triangles can be drawn as lattice triangles. Consequently, an integer triangle is Heronian if and only if it