Đáp án:
Giải thích các bước giải:
a) -1/10 + 2/5x + 7/20 = 1/10
=> 2/5x = 1/10 + 1/10 - 7/20
=> 2/5x = -3/20
=> x = -3/20 : 2/5
=> x = -3/8
Vậy x = -3/8
b) 1/3 + 1/2 : x = -1/5
=> 1/2 : x = -1/5 - 1/3
=> 1/2 : x = -8/15
=> x = -8/15 : 1/2
=> x = -16/15
Vậy x = -16/15
c) -2/3 : x + 5/8 = -7/12
=> -2/3 : x = -7/12 - 5/8
=> -2/3 : x = -19/24
=> x = -2/3 : -19/24
=> x = 16/19
Vậy x = 16/19
d)
=> 1/2x + 5/2 = 7/2x - 3/4
=> 1/2x - 7/2x = -3/4 - 5/2
=> -3x = -13/4
=> x = -13/4 : (-3)
=> x = 13/12
Vậy x = 13/12
e) 2/3x - 2/5 = 1/2x - 1/3
=> 2/3x - 1/2x = -1/3 + 2/5
=> 1/6x = 1/15
=> x = 1/15 : 1/6
=> x = 2/5
Vậy x = 2/5
f) 1/3x + 2/5 (x+1) = 0
=> 1/3x + 2/5x + 1 = 0
=> 1/3x + 2/5x = -1
=> 11/15x = -1
=> x = -1 : 11/15
=> x = -15/11
Vậy x = -15/11
