Right angle Right angle In geometry and trigonometry, a right angle is an angle of exactly 90° (degrees), corresponding to a quarter turn. If a ray is placed so that its endpoint is on a line and the adjacent angles are equal, then they are right angles. The term is a calque of Latin "angulus rectus"; here "rectus" means "upright", referring to the vertical perpendicular to a horizontal base line. Closely related and important geometrical concepts are perpendicular lines, meaning lines that form right angles at their point of intersection, and orthogonality, which is the property of forming right angles, usually applied
Poem of the Right Angle Poem of the Right Angle The Poem of the Right Angle ("Le Poeme de l'Angle Droit") is a series of 19 paintings and corresponding writings composed by the influential Swiss-French architect Le Corbusier between 1947 and 1953. Aside from his seminal manifesto "Toward an Architecture", "The Poem of the Right Angle" is considered to be his most lucid synthesis of personal maxims. "The Poem of the Right Angle" was composed over a period of seven years, from 1947-1953. The paintings are arranged symmetrically in seven rows, or "zones" and read across, in order, 5, 3, 5, 1, 3, 1, 1