History [edit]. In 1938, polytetrafluoroethylene (DuPont brand name Teflon) was discovered by accident by a recently hired DuPont Ph.D., Roy J. Plunkett. While working with tetrafluoroethylene gas, he noticed that a previously-pressurized cylinder had no pressure remaining.
Triangle Sides Calculator. This calculator calculates for the length of one side of a right triangle given the length of the other two sides. A right triangle has two sides perpendicular to each other. Sides a and b are the perpendicular sides and side c is the hypothenuse. Enter the length of any two sides and leave the side to be calculated blank. Please check out also the Regular Triangle Calculator and the Irregular Triangle Calculator.
Another interesting right triangle is the 30-60-90 degree triangle. The ratio of this triangle's longest side to its shortest side is two to one.. That is, the longest side is twice as long as the shortest side. It too is manufactured in plastic and widely used in design, drawing, and building applications.