9一0.9(x一0.9)=0.9
问题描述:
9一0.9(x一0.9)=0.9
答
10-(x-0.9)=1
x=9-0.9=8.1x=9+0.9=9.9
9一0.9(x一0.9)=0.9
10-(x-0.9)=1
x=9-0.9=8.1x=9+0.9=9.9