Answer:
An angle is the union of two rays meeting at a common point called the vertex. The two rays are called the terminal and the initial sides of an angle.
A horizontal line is sometimes called the real line. This line is divided into two equal rays by a point called the origin denoted as 0. The right ray of the horizontal line is usually the start of measuring angles. Angles between 0 to 90° is said to terminate in quadrant 1; 90° to 180° in quadrant II, 180° to 270° in quadrant III, and 270° to 360° in quadrant IV: 360° to 450° in quadrant ; etc.
Kinds of Angles
1. Acute angel - an angle between 0° to 90°
2. Right angle - an angle measuring exactly 90°
3. Obtuse angle - an angle measuring between 90° to 180°
4. Straight angle - an angle measuring exactly 180°
5. Reflex angle - an angle measuring between 180° and 360°
