如图，ABCD是直角梯形，上底AD是12厘米，高CD是7.2厘米，阴影部分的面积是7.2平方厘米，求梯形ABCD的面积．
直接写出得数．+=﹣+=+=﹣=+=+=++=﹣=+= 3﹣﹣=
直接写出得数﹣=﹣=﹣=+=+=﹣=+=﹣=
直接写出得数．+=﹣=+=﹣= 10﹣﹣=====．
直接写得数===== 1﹣= 1﹣==
直接写出得数.+= 1﹣=﹣= 2.5×3.8×4=+= 10﹣9.12=+0.25= 0.65×9+0.65=
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= 10﹣9.12=
+0.25= 0.65×9+0.65=
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