Welcome to the exciting world of geometry! Ahead of you lie many exciting discoveries that will help you
learn more about the world. Geometry is used in many areas—from art to science. For example, geometry
plays a key role in construction, fashion design, architecture, and computer graphics. This course focuses
on the main ideas of geometry that are the foundation of applications of geometry used everywhere. In this
chapter, you’ll study the basic elements of geometry. Later you will prove things about geometric shapes
using the vocabulary and ideas in this chapter—so make sure that you completely understand each of the
concepts presented here before moving on.