(x+3)/2-(0.4x-1)/0.5=-2.5
问题描述:
(x+3)/2-(0.4x-1)/0.5=-2.5
答
x+3-(0.4x-1)×4=-5
x+3-1.6x+4=-5
-0.6x+7+5=0
0.6x=12
x=20