请生成上面解题的视频---**Extraction Content:** **Problem 1:** * **Question Stem:** 1. 如图, Rt△ABC中, ∠B=90°, 若AD=15, CD=10, AC=20, 求AB的长 * **Diagram Description:** * Type: Geometric figure (triangle). * Main Elements: * Points: Labeled A, B, C, D. * Lines: Line segments AB, BC, AC forming a triangle ABC. Line segment AD connects vertex A to point D on side BC. * Angles: Angle at vertex B is marked with a right angle symbol (90°). ∠B=90°. * Relative Position: Triangle ABC is a right triangle with the right angle at B. Point D is on the side BC. * **Given Values:** AD=15, CD=10, AC=20. * **To Find:** AB的长 (the length of AB). **Problem 2:** * **Question Stem:** 2. 如图, ∠AEF=∠AS°, ∠ADB=37°, DE=8.5, 求点A到DE的距离 * **Diagram Description:** * Type: Geometric figure. * Main Elements: * Points: Labeled A, B, D, E, F. * Lines: Line segments AD, DE, EF, AF. Line segment BD is part of line segment AD. * Angles: Angle ∠ADB is marked with the value 37°. Angle ∠AEF is marked with the value 143° in the diagram. * Relative Position: Point B is on the line segment AD. * **Given Values:** ∠AEF=∠AS° (text, likely typo), ∠ADB=37°, DE=8.5. Diagram shows ∠AEF=143°. * **Other Relevant Text:** (Sin37°≈0.60, Cos37°≈0.80, tan37°≈0.75) * **To Find:** 点A到DE的距离 (the distance from point A to line DE).