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Definition1

Title: Line & Rays

Grade 4+ Lesson s1-l2

Explanation: The best way to understand geometry is by looking at some definitions. Take turns and read each definition for easy understanding.

Definition

Topics → Definition Example1

Definition: Line

A-line has no endpoints and can be extended on both sides.
It is a one-dimensional object with no thickness, width, or depth.
The symbol of a line is ↔.
*Types of lines are Parallel, Perpendicular, and Intersecting lines.

$1$

Explanation:

Two lines that lie in the same plane and never intersect are called parallel lines.
Lines that cross or intersect at a single point are called intersecting lines.
Lines that intersect at a right angle (90 degrees) are called perpendicular lines.

Definition: Ray

A ray is a part of a line that has one endpoint (i.e., starting point), and it extends in one direction endlessly.

$2$

Explanation:

P" is the origin of the ray, while "Q" is the point it passes through. The direction of travel is shown by an arrow above the points as \$\vec(PQ)\$.