Angle Definition:
An angle is the figure formed byWrite an angle using the ∠ symbol
two rays meeting at a common
end point called a vertex.
Two rays, BA and BC intersect at vertex B to form the angle in the image
2 ways to refer to this angle:
∠ ABC∠ B
Angle Measurement:
Angles are measured using degrees.6 types of angles:
0° ≤ Acute Angle < 90°Right Angle measures 90°
90° < Obtuse Angle < 180°
Straight Angle measures 180°
180° < Reflex Angle < 360°
Complete Angle measures 360°
Positive and Negative Angle Direction
Positive Angles:
Positive angles go counter-clockwiseSee +α in the picture above.
This is the opposite direction that clocks go
Negative Angles:
Negative angles go counter-clockwiseSee -α in the picture above.
This is the same direction that clocks go
