An angle is a geometric figure formed by two rays.
Bisector of Angle: A line which divides an angle into two equal parts.
Types of Angles:
Reflex angle: It is greater than 180° and less than 360°.
Positive and Negative angles:
Positive angles are the angles made by rotating counter clockwise whereas negative angles are made by rotating anti clockwise.
Example: Suppose an angle of 30 degree is made in clockwise direction. Then the angle is -30°.
-30° can also be written as 360° - 30° = 330°
1) Find angle P
Answer: Angle on a straight line is 180°
P + 20° + P + P + 10° = 180°
3P + 30° = 180°
3P = 150°
2) Find < Q
P + Q = 180°
25° + Q = 180°
Q = 155°