a) 3/4 – 2/15x = 29/60 b) 7/5 – 2/5x = 1-3/20 c) 30% . x – x + 5/6 = 1/3 d) 3/4x – 1/4 = 2(x-3 ) + 1/4x 20/08/2021 Bởi Peyton a) 3/4 – 2/15x = 29/60 b) 7/5 – 2/5x = 1-3/20 c) 30% . x – x + 5/6 = 1/3 d) 3/4x – 1/4 = 2(x-3 ) + 1/4x
a) 3/4 – 2/15x = 29/60 -2/15x = 29/60 – 3/4 -2/15x = -4/15 x = -4/15 : -2/15 x = 2 Vậy x = 2 b) 7/5 – 2/5x = 1 – 3/20 -2/5x = 17/20 – 7/5 -2/5x = -11/20 x = -11/20 : -2/5 x = 11/8 Vậy x = 11/8 c) 30%. x – x + 5/6 = 1/3 (30% – 1). x = 1/3 – 5/6 -7/10x = -1/2 x = -1/2 : -7/10 x = 5/7 Vậy x = 5/7 d) 3/4x – 1/4 = 2. (x – 3 ) + 1/4x 3/4x – 1/4x – 2. (x – 3) = 1/4 1/2x – 2x + 2. 3 = 1/4 -3/2x + 6 = 1/4 -3/2x = 1/4 – 6 -3/2x = -23/4 x = -23/4 : -3/2 x = 23/6 Vậy x = 23/6 Bình luận
Đáp án:
Giải thích các bước giải:
a) 3/4 – 2/15x = 29/60
-2/15x = 29/60 – 3/4
-2/15x = -4/15
x = -4/15 : -2/15
x = 2
Vậy x = 2
b) 7/5 – 2/5x = 1 – 3/20
-2/5x = 17/20 – 7/5
-2/5x = -11/20
x = -11/20 : -2/5
x = 11/8
Vậy x = 11/8
c) 30%. x – x + 5/6 = 1/3
(30% – 1). x = 1/3 – 5/6
-7/10x = -1/2
x = -1/2 : -7/10
x = 5/7
Vậy x = 5/7
d) 3/4x – 1/4 = 2. (x – 3 ) + 1/4x
3/4x – 1/4x – 2. (x – 3) = 1/4
1/2x – 2x + 2. 3 = 1/4
-3/2x + 6 = 1/4
-3/2x = 1/4 – 6
-3/2x = -23/4
x = -23/4 : -3/2
x = 23/6
Vậy x = 23/6