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.
The acute triangle is composed of three acute angles, the same as saying that all three of its angles are smaller than 90Â°. 1  A right triangle (or right-angled triangle) has one 90Â° internal angle (a right angle). 2  The side opposite to the right angle is the hypotenuse; it is the longest side in the right triangle.