 # What is an Angle

## Angle Definition:

An angle is the figure formed by
two rays meeting at a common
end point called a vertex.
Write an angle using the ∠ symbol Two rays, BA and BC intersect at vertex B to form the angle in the image

∠ 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-clockwise
See +α in the picture above.
This is the opposite direction that clocks go

## Negative Angles:

Negative angles go counter-clockwise
See -α in the picture above.
This is the same direction that clocks go

### How does the What is an Angle Calculator work?

Free What is an Angle Calculator - This lesson walks you through what an angle is and how to use it

### What 3 concepts are covered in the What is an Angle Calculator?

angle
the figure formed by two rays, called the sides of the angle, sharing a common endpoint, called the vertex of the angle.
geometry
study of math dealing with shapes, space, and properties of space
what is an angle