A right triangle (American English) or right-angled triangle (British English) is a triangle in which one angle is a right angle (that is, a 90- degree angle). The relation between the sides and angles of a right triangle is the basis for trigonometry. The side opposite the right angle is called the hypotenuse (side c in the figure). The sides adjacent to the right angle are called legs (or catheti, singular: cathetus).
Who was the first person to invent television? The first person to invent a fully functional television was Philo Taylor Farnsworth, an amateur inventor from Idaho. He publicly displayed his invention in 1927 but had conceived of the technology as early as 1921, when he was only 14 years old.
John Logie Baird invented and introduced the first TV system in London, England on January 26, 1926. To scan image, Baird used double spiral lenses in this electronic device. The first TV only featured 30 lines, which was one of the reasons why Baird decided to develop an upgraded version. The inventor established a company named Baird Television Development Company. The corporation successfully transmitted a TV signal from London to New York in 1928.