(x-30)[600-10(x-40)] 结果X=50

问题描述:

(x-30)[600-10(x-40)] 结果X=50
(x-30)[600-10(x-40)]=10000

(x-30)[600-10(x-40)]=10000
整理得x2-130x+4000=0
(x-50)(x-80)=0
解得x1=50,x2=80
当x=50时,600-10(x-40)=500