Lines
A line is a straight path that extends infinitely in both directions. It is one-dimensional and has no thickness.
Lines are fundamental elements in geometry and serve as the foundation for various geometric concepts.
Types of Lines:
- Straight Line (or Line Segment): A straight path that extends infinitely in both directions. A line segment is a finite portion of a straight line.
- Ray: A part of a line that has one endpoint and extends infinitely in one direction.
- Parallel Lines: Lines that are always the same distance apart and will never intersect.
- Perpendicular Lines: Lines that intersect at a right angle (90 degrees).
Angles:
An angle is formed by two rays or line segments that share a common endpoint. The common endpoint is called the vertex, and the rays are the sides of the angle.
Types of Angles:
- Acute Angle: An angle measuring less than 90 degrees.
- Right Angle: An angle measuring exactly 90 degrees.
- Obtuse Angle: An angle measuring more than 90 degrees but less than 180 degrees.
- Straight Angle: An angle measuring exactly 180 degrees.
- Reflex Angle: An angle measuring more than 180 degrees but less than 360 degrees.