Giải thích các bước giải:
3, 1/4x - 3/4 = - 1/1/2x + 1
<=> 1/4x - 3/4 = - 3/2x + 1
<=> 1/4x + 3/2x = 1 + 3/4
<=> 7/4x = 7/4
<=> x = 7/4 : 7/4
<=> x = 1
Vậy x = 1
4, - 1/2 - 2/3x = 1/4 + x
<=> - 2/3x - x = 1/4 + 1/2
<=> - 5/3x = 3/4
<=> x = 3/4 : (- 5/3)
<=> x = 3/4 . (- 3)/5
<=> x = - 9/20
Vậy x = - 9/20