x/90+2.5=x/50 怎么解
问题描述:
x/90+2.5=x/50 怎么解
答
x/90+2.5=x/50
(x/90+2.5)*450=x/50*450
5x+1125=9x
1125=9x-5x
4x=1125
x=1125/4
x=281.25