In geometry, a line is a fundamental concept that represents a straight one-dimensional figure that extends infinitely in both directions. It has no thickness, width, or curvature, and is typically defined by at least two points. Lines can be described using a variety of properties: 1. **Definition**: A line is determined by any two distinct points on it.
In the context of geometry, particularly when discussing triangles, "straight lines" generally refer to the sides of a triangle. A triangle is defined by three straight lines that connect three points, known as vertices, in a two-dimensional plane. These straight lines meet the following criteria: 1. **Straightness**: Each side is a straight line segment connecting two vertices. 2. **Consecutive**: Each side is adjacent to two other sides, forming the perimeter of the triangle.
