Two equilateral triangles are congrument. if they have ______ sides .

Answer

To determine the condition under which two equilateral triangles are congruent, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Equilateral Triangles**:
- An equilateral triangle is a triangle where all three sides are of equal length, and all three angles are equal to 60 degrees.

2. **Definition of Congruence**:
- Two figures (in this case, triangles) are said to be congruent if they have the same shape and the same size. This means that all corresponding sides and angles must be equal.

3. **Analyzing the Given Triangles**:
- We have two equilateral triangles. Since they are equilateral, we know that each triangle has equal sides and equal angles.

4. **Condition for Congruence**:
- For the two equilateral triangles to be congruent, not only must they be of the same shape (which they are, since both are equilateral), but they must also have sides of equal length.

5. **Conclusion**:
- Therefore, two equilateral triangles are congruent if they have equal sides.

### Final Answer:
Two equilateral triangles are congruent if they have **equal sides**.

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