I have a trapezoid where the height is 16m, the base is 20m,and the area is 224m squared. what is the legnth of the other base

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The area is equal to the height times the average of the bases. Since the Area is 224 and the height is 16, the average of the bases must be 14. (16 * 14 = 224). Since the average of the bases must be 14, and one is 20, then the other must be 8.