0.8x+0.2(7-x)=3.8 怎么解
问题描述:
0.8x+0.2(7-x)=3.8 怎么解
答
0.8x+0.2X7-0.2Xx=3.8
0.8x-0.2x=3.8-1.4
0.6x=2.4
x=4