a 180 degrees angle is sometimes called a straight angle.Explain why that name makes sense.
if you take any angle, and move the sides so the angle is 180 degrees, it makes a straight line. Look at your protractor...
http://www.mathsisfun.com/geometry/images/protractor.gif
The term "straight angle" can be derived from its geometric properties. To understand why a 180-degree angle is commonly known as a straight angle, we need to look at the characteristics of this specific angle.
1. Definition of angles: In geometry, an angle is formed by two rays that originate from the same point, called the vertex. The rays are also known as the sides of the angle.
2. Straight line: A straight line is a line that does not curve or bend. It is an extension of infinitely many points in both directions. It can also be thought of as the shortest distance between two points.
When we consider these two concepts, it becomes evident why a 180-degree angle is called a straight angle:
1. Linearity: A 180-degree angle forms a straight line. It consists of two rays that extend in opposite directions from the vertex and align with each other. The rays span across a complete half-circle, resembling a straight line.
2. Straightness: A straight line is the simplest and most direct path between two points. Similarly, a 180-degree angle has no deviation or curvature. Its rays align perfectly, without any bending or inclination.
Hence, due to its inherent linearity and resemblance to a straight line, a 180-degree angle is referred to as a straight angle.