A triangle whose all sides are equal is called

Options

A. an equilateral triangle
B. an acute triangle
C. a right triangle
D. an isosceles triangle

Answer

To solve the question "A triangle whose all sides are equal is called," we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Types of Triangles**:
- Triangles can be classified based on the lengths of their sides. There are three main types: equilateral, isosceles, and scalene.

2. **Define Each Type**:
- **Equilateral Triangle**: A triangle where all three sides are of equal length.
- **Isosceles Triangle**: A triangle where two sides are of equal length, and one side is different.
- **Scalene Triangle**: A triangle where all three sides are of different lengths.

3. **Identify the Correct Type**:
- The question specifically asks for a triangle where all sides are equal. Based on our definitions, this matches the definition of an equilateral triangle.

4. **Conclusion**:
- Therefore, a triangle whose all sides are equal is called an **equilateral triangle**.

### Final Answer:
A triangle whose all sides are equal is called an **equilateral triangle**.

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