Giải thích các bước giải:
`2`
`a)(-1)/2+x=(-2)/3-1/(-4)`
`=>(-1)/2+x=-2/3+1/4`
`=>(-1)/2+x=-8/12+3/12`
`=>(-1)/2+x=-5/12`
`=>x=-5/12-(-1)/2`
`=>x=-5/12+1/2`
`=>x=-5/12+6/12`
`=>x=1/12`
Vậy `x=1/12`
`b)`
`(-1)/(-5)-x=(-2)/5-(-1)/(-4)`
`=>1/5-x=-2/5-1/4`
`=>1/5-x=-8/20-5/20`
`=>1/5-x=-13/20`
`=>x=1/5+13/20`
`=>x=4/20+13/20`
`=>x=17/20`
Vậy `x=17/20`
`c)`
`(-1)/2 x - 1/(-4)=(-2)/5-3/(-15)`
`=>-1/2 x + 1/4=-2/5+3/15`
`=>-1/2 x+1/4=-6/15+3/15`
`=>-1/2 x +1/4=-3/15`
`=>-1/2 x +1/4=-1/5`
`=>-1/2 x=-1/5-1/4`
`=>-1/2 x=-4/20-5/20`
`=>-1/2 x=-9/20`
`=>x=-9/20:(-1)/2`
`=>x=-9/20 . (-2)`
`=>x=9/10`
Vậy `x=9/10`
`d)`
`(-2)/(-3) x+2/(-9)=-2/3 -4/(-27)`
`=>2/3 x -2/9=-2/3+4/27`
`=>2/3 x-2/9=-18/27+4/27`
`=>2/3 x-2/9=-14/27`
`=>2/3 x = -14/27+2/9`
`=>2/3 x=-14/27 + 6/27`
`=>2/3 x=-8/27`
`=>x=-8/27:2/3`
`=>x=-8/27 . 3/2`
`=>x=-4/9`
Vậy `x=-4/9`
