请给一名小学2年级学生讲解这道题。她不会做。---**Question Stem:** 求长方形 ABCD 的面积 **Chart/Diagram Description:** * **Type:** Geometric figure. * **Main Elements:** * A rectangle labeled ABCD. Vertices are labeled A (top left), B (bottom left), C (bottom right), D (top right). * Points E and F are located on the top side AD of the rectangle, with E to the left of F. * Point G is located above the rectangle. * Three triangles are formed and colored: * Triangle ABE (colored green) with the number 6 inside it. * Triangle EFG (colored blue) with the number 8 inside it. * Triangle FCD (colored orange) with the number 12 inside it. * Lines are drawn connecting A-B, B-C, C-D, D-A (forming the rectangle). * Lines are drawn connecting A-E, E-B (forming triangle ABE). * Lines are drawn connecting E-G, G-F, F-E (forming triangle EFG). * Lines are drawn connecting F-C, C-D (forming triangle FCD). Note that FD is also a side of triangle FCD. * Lines are drawn connecting G-A and G-D (not part of the colored triangles, but show G's relation to A and D). * Areas of the three colored triangles are given: Area(△ABE) = 6, Area(△EFG) = 8, Area(△FCD) = 12. * The question asks for the area of rectangle ABCD.