1. **Problem statement:**
Given a figure with segments (AB) parallel to (CD) and (EF), angles BAC = 50° and CFE = ESC, find the measures of angles DCF and CFE.
2. **Step 1: Understand the parallel lines and transversal properties.**
Since (AB) is parallel to (CD) and (EF), and FCA and ES are transversals, corresponding and alternate interior angles are equal.
3. **Step 2: Find angle DCF.**
Angle BAC = 50° is given.
Since (AB) is parallel to (CD), angle BAC corresponds to angle DCF (alternate interior angles).
Therefore, $$\angle DCF = 50^\circ$$.
4. **Step 3: Find angle CFE.**
Given that $$\angle CFE = \angle ESC$$.
Since (EF) is parallel to (AB) and (CD), and ES intersects CD at S, angles CFE and ESC are equal by corresponding angles property.
5. **Step 4: Justify the measure of angle CFE.**
Because $$\angle ESC = \angle CFE$$ and $$\angle DCF = 50^\circ$$, and considering the triangle formed by points C, F, E, the sum of angles in triangle CFE is 180°.
6. **Step 5: Show that (ES) is parallel to (FC).**
Since $$\angle CFE = \angle ESC$$ and these are alternate interior angles formed by transversal FE crossing lines ES and FC, by the converse of the alternate interior angles theorem, (ES) is parallel to (FC).
**Final answers:**
$$\angle DCF = 50^\circ$$
$$\angle CFE = \angle ESC$$ (equal by given and parallel line properties)
$$(ES) \parallel (FC)$$ by alternate interior angles theorem.
Parallel Angles 9B8C15
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