Angles

In Euclidean geometry, an angle is the figure formed by two rays, called the sides of the angle, sharing a common endpoint, called the vertex of the angle. Angles formed by two rays lie in the plane that contains the rays. Angles are also formed by the intersection of two planes. These are called dihedral angles. Two intersecting curves define also an angle, which is the angle of the tangents at the intersection point. For example, the spherical angle formed by two great circles on a sphere equals the dihedral angle between the planes containing the great circles.

A member of a Germanic people, originally inhabitants of what is now Schleswig-Holstein, who migrated to England in the 5th century ad. The Angles founded kingdoms in Mercia, Northumbria, and East Anglia and gave their name to England and the English.

Right angle: An angle whose measure is 90°, is called a right angle. Two lines that meet at a right angle are said to be perpendicular. Acute angle: An angle whose measure is less than 90°, is called an acute angle. Obtuse angle: An angle whose measure is greater than 90° and less than 180°, is called an obtuse angle. Straight angle: An angle whose measure is 180° is called a straight angle. Reflex angle: An angle whose measure is more than 180° but less than 360°, is called a reflex angle. Complete angle: An angle whose measure is 360° is called a complete angle. Zero angle: An angle whose measure is 0° is called a zero angle.

i do not know