Ray
Definition of a Ray

• A Ray is a part of a Line that begins at a particular point (called the endpoint) and extends endlessly in one direction. A Ray is also called half-line.

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How do we name a Ray?

• A Ray is named based on the Direction in which it extends.
• A Ray is named with its endpoint in the First place, followed by the Direction in which its moving.
• In the example shown below, P is the endpoint and Q is the point towards which the Ray extends. So, the Ray PQ is represented as:

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• Look at another example. This Ray will be called QP as it starts at Q and extends towards P. So, the Ray QP is represented as:

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Solved Example on Ray

Which of the following is a ray?

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Solution:
Step 1: The definition of a Ray states that "A Ray is a part of a Line that begins at a particular point (called the endpoint) and extends endlessly in one direction."
Step 2: As per the defition of a ray, among the figures given only Figure 2 represents a ray.

Related Terms for Ray

• Endpoint
• Part of a Line
• Angle
• Vertex

Additional Links for Ray

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