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
The Three Degrees Live The Three Degrees Live The Three Degrees Live is a 1976 live album by Philadelphia-based female vocal trio The Three Degrees who scored major international success with 'When Will I See You Again?'. The album charted at #34 in the US R&B Album chart and at #199 in the Billboard Top 200. During a UK tour in 1975, The Three Degrees performed at Bailey's in Leicester, England, and the evening's concert was recorded and subsequently released by Philadelphia International Records as "The Three Degrees Live". The setlist for the concert was typical of what the group was doing at that