解方程!5X-2*0.8=33.42(X-7.5)=181.8X=0.8=20.8啊,抱歉,最后是:1.8+0.8X=2
4个回答

5X-2*0.8=33.4,

5X=33.4+1.6,

5X=35,

X=7;

2(X-7.5)=18 ,

2X-15=18,

2X=18+15,

2X=33,

X=33/2;

应该是"1.8X+0.8=20.8"吧?(可能是把加号写成了等号了,因为加号是等号的上档键)

1.8X+0.8=20.8,

1.8X=20.8-0.8,

1.8X=20,

X=20/1.8,

X=20*(5/9)=100/9.