求阴影部分的面积。（单位：厘米）8{:s3X'n1n9y
8{:s3X'n1n9y
算式：提示9b-I6P-y,i9J6g0c8{:s3X'n1n9y
答：阴影部分的面积是7B(n2p0e平方厘米。8{:s3X'n1n9y