Right angle of what a right angle is, namely two straight lines intersecting to form two equal and adjacent angles. The straight lines which form right angles are called perpendicular. Euclid uses right angles in definitions 11 and 12 to define acute angles (those smaller than a right angle) and obtuse angles (those greater than a right angle). Two angles are called complementary if their sum is a right angle. Book 1 Postulate 4 states that all right angles are equal, which allows Euclid to use a right angle as a unit to measure other angles with. Euclid's commentator Proclus gave a
Silk Degrees Silk Degrees Silk Degrees is the seventh album by Boz Scaggs, released on Columbia Records in 1976. The album peaked at No. 2 and spent 115 weeks on the "Billboard" 200. It has been certified five times platinum by the RIAA and remains Scaggs's best selling album. "Silk Degrees" spawned four singles. "It's Over", "Lowdown", and "Lido Shuffle" made the Top 40, while "What Can I Say" peaked at No. 42. The album was recorded at Davlen Sound Studios and Hollywood Sound Studios in Los Angeles. Among the accompanying musicians, David Paich, Jeff Porcaro, and David Hungate became members of