Chapter 5 Geometry

Section 5.2 Angles and Angle Measurement

5.2.1 Introduction

Lines intersecting at a point S divide the plane in a characteristic way. To describe how, the concept of an angle is introduced. The question how to measure angles can be answered in different ways, which in the end are all based on the subdivision of circles.
In this module, degree measure and radian measure are described.

Every coloured region represents one of the angles defined by the lines g and h.