Geometry is the most practical branch of mathematics that deals with shapes and sizes of figures and their properties. You have already learned about the basic elements of geometry – lines and angles. Let us recall their definition.

In geometry, lines are figures that are made up of infinite points extending indefinitely in both directions. Lines are straight and have negligible depth or width.

An angle is a figure in which two rays emerge from a common point. In this article, we will discuss some more related terminologies and definitions related to lines and angles.

## Lines

Basic Terms and Definitions

It is to be noted that, three points can be either collinear or non-collinear, but not both together at a same time.

## Angles

Basic Terms and Definitions

- When two lines intersect each other, the two opposite pairs of angles formed are called vertically opposite angles. In the following figure, ∠A and ∠B are vertically opposite angles. Another pair is ∠C and ∠D.

To solve more problems on Lines and Angles visit our page. Chapter wise solution for NCERT examples for the chapter Lines and Angles is also provided. Study more to have a better understanding for the topic.

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