0.8*50x>0.7*50(x+4) 0.8*50x=0.7*50(x+4) 0.8*50x

问题描述:

0.8*50x>0.7*50(x+4) 0.8*50x=0.7*50(x+4) 0.8*50x
(1)0.8*50x>0.7*50(x+4)
(2)0.8*50x=0.7*50(x+4)
(3)0.8*50x

0.8*50x>0.7*50(x+4)
40x>35(x+4)
40x>35x+140
5x>140
x>28
0.8*50x=0.7*50(x+4)
40x=35(x+4)
40x=35x+140
5x=140
x=28
0.8*50x