Short Answer 
An obtuse angle is defined as an angle that measures between 90 and 180 degrees, making it wider than a right angle. Examples include angles of 120, 135, and 160 degrees. Recognizing obtuse angles is crucial for understanding geometry and analyzing shapes.
Step 1: Understand the Definition of Obtuse Angles
An obtuse angle is defined as any angle that measures greater than 90 degrees but less than 180 degrees. This means that obtuse angles are wider than right angles, which are precisely 90 degrees. Recognizing this distinction is crucial in geometry for identifying various angle types and their roles in shapes.
Step 2: Identify Examples of Obtuse Angles
To better understand obtuse angles, it is helpful to look at some specific examples. Here are some common angles that qualify as obtuse:
- An angle measuring 120 degrees
- An angle measuring 135 degrees
- An angle measuring 160 degrees
These examples show the range of measurements that obtuse angles can have and help solidify your understanding of this type of angle.
Step 3: Importance of Recognizing Obtuse Angles
Recognizing and naming obtuse angles is essential for studying geometry as it contributes to a deeper understanding of geometrical shapes and their properties. By distinguishing obtuse angles from other types, such as acute and right angles, you can analyze and classify shapes more effectively. This knowledge also supports various mathematical applications, from simple shapes to complex constructions.