(10X+20)/50- (12X-30)/54=0.5

问题描述:

(10X+20)/50- (12X-30)/54=0.5

(10X+20)/50- (12X-30)/54=0.5两边同乘2:2(10X+20)/50-2(12X-30)/54=0.5*2(10X+20)/25- (12X-30)/27=1两边同乘25*27:27(10X+20)- 25(12X-30)=25*27270X+20*27-300X+25*30=25*27-30X=25*27-20*27-25*30-30X=27(25-2...