`c)1/4x+2/5=7/5`
`=>1/4x=7/5-1/5=1`
`=>x=1:1/4=4`
Vậy `x=4`
`a)2x-2/3=-3/4`
`=>2x=-3/4+2/3=-1/12`
`=>x=-1/24`
Vậy `x=-1/24`
`b)x:3/4+1/4=-2/3`
`=>x:3/4=-2/3-1/4=-11/4`
`=>x=-11/4 xx 3/4=-33/16`
Vậy `x=-33/16`
Giải:
a)2x-2/3=-3/4
2x =-3/4+2/3
2x =-1/12
x =-1/12:2
x =-1/24
b)x:3/4+1/4=-2/3
x:3/4 =-2/3-1/4
x:3/4 =-11/12
x =-11/12.3/4
x =-11/16
c)1/4x+2/5=7/5
1/4x =7/5-2/5
1/4x =1
x =1:1/4
x =4
d)|x|.5-2=-3/5
|x|.5 =-3/5+2
|x|.5 =7/5
|x| =7/5:5
|x| =7/25
⇒x=7/25 hoặc x=-7/25
Chúc bạn học tốt!