As shown in the figure, two congruent right triangles are overlapped, and one of them is translated to the position of △ def along the direction from point B to C, ab = 10, do = 4, and the translation distance is 6, then the shadow area is () A. 48B. 96C. 84D. 42

As shown in the figure, two congruent right triangles are overlapped, and one of them is translated to the position of △ def along the direction from point B to C, ab = 10, do = 4, and the translation distance is 6, then the shadow area is () A. 48B. 96C. 84D. 42

According to the properties of translation, be = 6, de = AB = 10, ∧ OE = de-do = 10-4 = 6, ∧ s quadrilateral odfc = s trapezoid abeo = 12 (AB + OE) · be = 12 (10 + 6) × 6 = 48