# Why must there be at least two lines on any given plane?

Updated on January 9, 2024

Answer: To define a plane

## Basic Geometry Concepts

A plane in geometry is a flat, two-dimensional surface that extends infinitely in all directions. For a plane to be defined, at least two non-parallel lines are required. These lines must lie flat on the surface and provide a reference or framework for the plane. The concept of lines and planes is fundamental in geometry and is crucial for understanding spatial relationships and properties. In fields such as architecture, engineering, and design, the principles of geometry, including the concepts of lines and planes, are applied to create and understand three-dimensional structures and spaces.

## FAQ on Geometry Fundamentals

### What defines a line in geometry?

A series of points extending in two opposite directions

### What is the difference between a line and a ray?

A ray has one endpoint; a line does not

### What is a parallel line?

Lines that never intersect and are equidistant at all points