第九题解答---Here is the extraction of content from the image:
**Question 9**
**Question Stem:**
9. 如图, 已知 D 是△ABC 的边 BC 上任意一点, DE∥AC, DF∥AB. 求证: ∠AED = ∠AFD.
**Chart/Diagram Description:**
* **Type:** Geometric figure (Triangle).
* **Main Elements:**
* A triangle labeled ABC.
* Point D is located on the side BC.
* A line segment DE is drawn from D to the side AB, intersecting AB at point E.
* A line segment DF is drawn from D to the side AC, intersecting AC at point F.
* Line segment DE is parallel to line segment AC (DE∥AC).
* Line segment DF is parallel to line segment AB (DF∥AB).
* Angles ∠AED and ∠AFD are marked.
* **Labels:** Vertices A, B, C. Points D, E, F.
* **Title/Annotation:** 第 8 题图 (Figure for Question 8). Note: This label appears next to the figure, even though it corresponds to question 9.
**Question 10**
**Question Stem:**
10. 一个角的两条边与另一个角的两条边分别平行, 其中一个角的度数为 36°, 那么另一个角的度数为_______.
**Question 11**
**Question Stem:**
11. 如图, 已知在△ABC 中, ∠ABC 和 ∠ACB 的平分线相交于点 D, EF 过点 D, 且 EF∥BC, 交 AB 于点 E, 交 AC 于点 F. 求证: EF = BE + CF.
**Chart/Diagram Description:**
* **Type:** Geometric figure (Triangle).
* **Main Elements:**
* A triangle labeled ABC.
* Line BD is the angle bisector of ∠ABC.
* Line CD is the angle bisector of ∠ACB.
* Point D is the intersection of BD and CD.
* A line segment EF passes through point D.
* Point E is on side AB and point F is on side AC.
* Line segment EF is parallel to line segment BC (EF∥BC).
* **Labels:** Vertices A, B, C. Points D, E, F.
* **Title/Annotation:** 第 11 题图 (Figure for Question 11).