Question

What do we call 180° angle?

• A. Obtuse angle
• B. Straight angle
• C. Equilateral angle
• D. None of these

Hint:

Associate the name with the shape: A 90° angle forms a perfect corner (Right angle). A 180° angle forms a straight line (Straight angle).

Answer 1

The Correct Option is B

Step 1: Understanding the Concept
The question asks for the specific name of an angle that measures exactly 180°.
Step 2: Detailed Explanation
Let's define the angle types in the options:
Obtuse angle: An angle that is greater than 90° but less than 180°.
Straight angle: An angle that is exactly 180°. It is called a straight angle because it forms a straight line.
Equilateral angle: This term is not standard. An angle in an equilateral triangle is 60°. "Equilateral" refers to a shape with equal side lengths.
Based on the definitions, a 180° angle is called a straight angle.