# Angles: The Backbone of Geometry and Mathematics

One cannot imagine how difficult it could have been for us if there were no discovery of angles done. Angles are one of those things which can be applied to everything, let it be a mathematical problem or life. Angles play a major role in building apartments, bridges, and many other things. Angles are two rays that meet at a common point. It is one of the most important things which needs to be known if one needs to excel in trigonometry. Angles have been used since ancient times. There are a large variety of angles that we study in mathematics, some of them are alternate exterior angles, interior angles, acute angles, etc. This article deals with different types of angles and gives information about how they differ from each other.

### The first type to differentiate between angles is measurement. Based on measurement, angles can be defined as:

1) Acute angle: The angles which measure less than ninety degrees can be termed under acute angle.

2) Obtuse angle: The angle which measures more than ninety degrees is termed the obtuse angle.

3) Right angle: When the angle between two rays is exactly ninety degrees. Then that angle is called the right angle.

4) Straight angles: The name itself defines the angle. The straight angle can be termed as a straight line whose angle is one-eighty degrees.

5) Reflex angles are those whose angles measure more than one-eighty degrees but less than three-sixty degrees.

### Listed below are different types of angles that are differentiated from other angles based on rotation:

1) Positive angles: These angles are those types of angles that are tilted or rotated in an anticlockwise direction from the base of the line. These types of angles are known as positive angles.

2) Negative angles: The negative angles are those types of angles whose angle from the base is rotated in the clockwise direction from the base of the line. Such types of angles are known as negative angles.

### Let’s discuss different types of angle pairs which we study in mathematics are:

1) Adjacent angle: The condition which needs to get satisfied for adjacent angle pairs is:

• The angles should have one common arm between them.
• The angles should have one common vertex between them.
• There should be two that are not common.

2) Complementary angles: When the addition that is the sum of the two angles is exactly equal to ninety degrees. These types of angles are known as complementary angles. For example, if the angle is 55° and 35° then they are known as a complement to each other.

3) Supplementary angles: When the sum that is the addition of two angles is equal to 180°. Then such types of angles can be said to be a supplement of each other. For example, one angle is 60° and the other one is 120°, then these are known as supplementary angles of each other.

4) Alternate exterior angles:  When two lines that are parallel to each other are transversed by a line and the angle that is formed on the external side of the lines. Such types of angles are said to alternate exterior angles.

5) Alternate interior angles: When a line that seems to pass through two lines that will not meet or in simple words are parallel to each other projects the angles that are formed at the same direction or position or on the same side of the transversal these type of angles are termed alternate interior angles and these angles are congruent. These angles are also known as linear pair of angles.

6) Vertical opposite angles: When two lines bisect each other then the angle that is formed on the opposite side of each other and the magnitude of the Angles are equal to each other, such types of angles can be called vertically opposite angles.

These were different types of angles that we study in mathematics. If the student gets difficulties in mathematics and wants to clear the doubts and wants to make weak concepts strong, then he can refer to a website known as Cuemath. It is one of the best sites for students which is helping students in various ways.