If `triangle ABC cong triangle DEF` then
`angle BCA =`_______

Answer

To solve the problem, we need to determine the value of angle BCA in triangle ABC given that triangle ABC is congruent to triangle DEF.

**Step-by-Step Solution:**

1. **Understanding Congruence**: We start with the information that triangle ABC is congruent to triangle DEF. This means that all corresponding sides and angles of these triangles are equal.

2. **Identifying Corresponding Angles**: In congruent triangles, the corresponding angles are equal. The angles in triangle ABC correspond to the angles in triangle DEF as follows:
- Angle A corresponds to Angle D
- Angle B corresponds to Angle E
- Angle C corresponds to Angle F

3. **Finding Angle BCA**: We are specifically interested in angle BCA, which is the same as angle C in triangle ABC. According to the congruence, angle C in triangle ABC will be equal to angle F in triangle DEF.

4. **Conclusion**: Therefore, we can conclude that:
\[ \text{Angle BCA} = \text{Angle C} = \text{Angle F} \]

**Final Answer**:
\[ \text{Angle BCA} = \text{Angle F} \]

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