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
Extouch triangle Extouch triangle In geometry, the extouch triangle of a triangle is formed by joining the points at which the three excircles touch the triangle. The vertices of the extouch triangle are given in trilinear coordinates by: or equivalently, where "a,b,c" are the lengths of the sides opposite angles "A, B, C" respectively, The triangle's splitters are lines connecting the vertices of the original triangle to the corresponding vertices of the extouch triangle; they bisect the triangle's perimeter and meet at the Nagel point. This is shown in blue and labelled "N" in the diagram. The Mandart inellipse is tangent to