Đáp án:
a) -2/3 - 1/3 * 2x - 5 =3/2
=>-1/3 * 2x=-2/3-3/2+5
=>-1/3 * 2x=-20/30-45/30+150/30
=>-1/3 * 2x=85/30
=>2x=85/30:(-1/3)
=>2x=85/30 x (-3)
=>x=8,5 x 1/2
=>x=85/20
Vậy x=85/20
b) 1/4*x+3/4=1/12
1/4 * x =1/12-9/12
1/4 *x=-8/12=-2/3
x=-2/3:1/4
x=-2/3 x 4
x=-8/3
Vậy x=-8/3
Giải thích các bước giải:
a) -2/3 - 1/3 * 2x - 5 =3/2
=>-1/3 * 2x=-2/3-3/2+5
=>-1/3 * 2x=-20/30-45/30+150/30
=>-1/3 * 2x=85/30
=>2x=85/30:(-1/3)
=>2x=85/30 x (-3)
=>x=8,5 x 1/2
=>x=85/20
Vậy x=85/20
b) 1/4*x+3/4=1/12
1/4 * x =1/12-9/12
1/4 *x=-8/12=-2/3
x=-2/3:1/4
x=-2/3 x 4
x=-8/3
Vậy x=-8/3
