Two line segment AB and CD are congruent.
If AB = 6 cm, then what is the length of CD?

Answer

To solve the problem step by step, we can follow this reasoning:

### Step-by-Step Solution:

1. **Understand the Concept of Congruence**:
- Congruent line segments are segments that have the same length.

2. **Identify the Given Information**:
- We are given that the line segment AB is 6 cm long.
- We are also told that line segments AB and CD are congruent.

3. **Apply the Definition of Congruence**:
- Since AB and CD are congruent, this means that the lengths of AB and CD are equal.

4. **Set Up the Equation**:
- From the information, we can write the equation:
\[ AB = CD \]

5. **Substitute the Known Length**:
- We know that \( AB = 6 \, \text{cm} \).
- Therefore, we can substitute this value into our equation:
\[ 6 \, \text{cm} = CD \]

6. **Conclude the Length of CD**:
- Hence, we find that:
\[ CD = 6 \, \text{cm} \]

### Final Answer:
The length of CD is 6 cm.

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