Ray Study Guide

A ray is a part of a line that has one endpoint and extends infinitely in one direction. It can be thought of as a straight line that starts at a particular point and goes on forever in one direction.

Study Guide for Ray:

1. Endpoint: A ray has one endpoint, which is the starting point of the ray. It is represented by a dot and labeled with a capital letter.
2. Naming a Ray: A ray is named by its endpoint and another point on the ray. The endpoint is always mentioned first when naming the ray.
3. Symbol: A ray is typically denoted by drawing an arrow on top of the line segment to indicate that it extends infinitely in one direction.
4. Opposite Rays: If two rays have the same endpoint and form a straight line, they are called opposite rays. Opposite rays are collinear and form a straight angle.
5. Notation: The notation for a ray can be represented as a single letter with an arrow on top, such as "→AB" to represent the ray starting at A and extending through B.

Understanding the concept of a ray is important in geometry and can help students in understanding the properties of lines and angles.