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 showed a working television system to the public in 1925. Baird was a Scottish engineer and inventor of the world's first working television system in Hastings, England, in 1923. His public demonstration subsequently took place in Selfridges, a department store in London England, during March 1925.