多边形面积求解动画，动态的添加三角形和矩形，将原本的图形转换为一个梯形，再用梯形的面积分别减去三角形和矩形面积，最终得到原本图形的面积。每个子图形闪烁显示计算公式，箭头引导观看计算步骤，绿色覆盖最终面积区域，右边同步显示算式推导过程。---**Question Stem:** 求阴影部分的面积。(单位: m) *Translation: Find the area of the shaded part. (Unit: m)* **Chart/Diagram Description:** * **Type:** Geometric figure illustrating a composite shape and its dimensions. * **Main Elements:** * The figure is a large, irregularly shaped polygon, resembling a stylized "M". It is composed of a larger outer trapezoid with an inverted triangle and a rectangle cut out from its interior. The remaining "M" shape is the shaded region. * **Outer Trapezoid:** * Upper base: 8 units. * Lower base: 15 units. * Height: 10 units (indicated by a vertical dashed line on the right side, extending from the top right vertex to the bottom base, with a right angle symbol). * **Unshaded Inverted Triangle:** * Base: 8 units (this base is the same as the upper base of the outer trapezoid). * Height: 4 units (indicated by a vertical dashed line from the top vertex of the triangle to its base). * **Unshaded Rectangle:** * Width (horizontal dimension): 7 units. * Height (vertical dimension): 5 units (indicated on the left side of the rectangle). * All dimensions are labeled with numerical values. Dashed lines indicate projections or heights. Right angle symbols indicate perpendicularity. **Other Relevant Text (Calculations/Solution Steps):** * **梯形面积** (Trapezoid Area): `(8 + 15) × 10 ÷ 2 = 115 (m²)` * **三角形面积** (Triangle Area): `8 × 4 ÷ 2 = 16 (m²)` * **长方形面积** (Rectangle Area): `5 × 7 = 35 (m²)` * **阴影部分面积** (Shaded Part Area): `115 - 16 - 35 = 64 (m²)` **Method Used:** 添补法 *Translation: Subtraction Method / Method of Completing (or Decomposing and Subtracting)*