Given that the shadow area is 50 square centimeters, find the area of triangle ABC
As shown in the figure: the midpoint of AB is D, the midpoint of AC is e, BC = 2DE, the height of triangle ABC = the height of triangle BDE × 2, so the area of triangle ABC is 50 × 2 × 2 = 100 × 2 = 200 (square centimeter). Answer: the area of triangle ABC is 200 square centimeter
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