如图BD=DC,∠BDA=45°,∠B=3∠C,求∠C---**Chart/Diagram Description:** * **Type:** Geometric figure (Triangle). * **Main Elements:** * **Points:** Points labeled A, B, C, and D. A is at the top vertex. B is at the bottom left vertex. C is at the bottom right vertex. D is a point on the line segment BC, between B and C. * **Lines:** Straight lines connecting the points: AB, BC, AC, and AD. * **Labels and Annotations:** Points are labeled A, B, C, D. There are small red dash markings on the line segment BD and on the line segment DC, indicating that BD and DC are equal in length (D is the midpoint of BC). * **Relative Position and Direction:** Triangle ABC is shown. Point D lies on the side BC. AD is a line segment inside triangle ABC, connecting vertex A to point D on side BC. Point A is above the line BC. Point B is to the left of point D, and point D is to the left of point C, all on the line BC. **Extraction Content Requirements:** Based on the image, there is no question stem, options, or other textual information present besides the geometric diagram itself. The diagram only shows a triangle ABC with a point D on BC such that BD = DC, suggesting D is the midpoint of BC and AD is a median of triangle ABC.