Two circles are congrument if they have _______ radii .

Answer

To solve the question, "Two circles are congruent if they have _______ radii," we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Congruence**:
- Congruent figures are those that have the same shape and size. For circles, this means they must have the same radius.

2. **Identifying the Circles**:
- Let's consider two circles, Circle A and Circle B.

3. **Comparing the Sizes**:
- To determine if Circle A and Circle B are congruent, we need to compare their sizes. The size of a circle is determined by its radius.

4. **Defining Radius**:
- The radius of a circle is the distance from the center of the circle to any point on its circumference.

5. **Conclusion**:
- If the radius of Circle A is equal to the radius of Circle B, then the two circles are congruent. Therefore, the answer to the question is: "Two circles are congruent if they have equal radii."

### Final Answer:
Two circles are congruent if they have **equal** radii.

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