用不同的方法计算下图的面积。（单位：dm）(r7[(W2l6?/o
(r7[(W2l6?/o
算式：提示'y-w*X5W4L:a;e+e1N(r7[(W2l6?/o
答：积是8@4h/V4?+L平方分米。(r7[(W2l6?/o
(r7[(W2l6?/o