Toán 3/5.x-2/3=-1/2 (1/2-x).2/3=1/8 |2.x-3/7|-1/2=3/4 2.x+1/3=x-5/2 30/06/2021 By Reagan 3/5.x-2/3=-1/2 (1/2-x).2/3=1/8 |2.x-3/7|-1/2=3/4 2.x+1/3=x-5/2
a) 3/5 . x – 2/3 = -1/2 b) (1/2 – x) . 2/3 = 1/8 3/5 . x = -1/2 + 2/3 1/2 – x = 1/8 : 2/3 3/5 . x = 1/6 1/2 – x = 3/16 x = 1/6 : 3/5 x = 1/2 -3/16 x = 5/18 x = 5/16 Vậy x = 5/18 Vậy x = 5/16 c) | 2.x – 3/7 | – 1/2 = 3/4 | 2.x – 3/7 | = 3/4 + 1/2 | 2.x – 3/7 | = 5/4 TH1 : 2.x – 3/7 = 5/4 TH2: 2.x – 3/7 = -5/4 2.x = 5/4 + 3/7 2.x = -5/4 + 3/7 2.x = 47/28 2.x = -23/28 x = 47/28 : 2 x = -23/28 : 2 x = 47/56 x = -23/56 Vậy x ∈ { 47/56 ; -23/56 } d) 2.x +$\frac{1}{3}$ = x – $\frac{5}{2}$ $\frac{6x + 1}{3}$ = $\frac{2x – 5}{2}$ 2(6x + 1) = 3(2x – 5) 12x + 2 = 6x – 15 6x – 12x = 15 + 2 -6x = 17 x = 17 : -6 x = $\frac{-17}{6}$ Vậy x = $\frac{-17}{6}$ Trả lời
Đáp án + Giải thích các bước giải: `3/5x-2/3=-1/2` `=>3/5x=-1/2+2/3` `=>3/5x=-3/6+4/6` `=>3/5x=1/6` `=>x=1/6:3/5` `=>x=1/6. 5/3` `=>x=5/18` `—` `(1/2-x).2/3=1/8` `=>1/2-x=1/8:2/3` `=>1/2-x=1/8. 3/2` `=>1/2-x=3/16` `=>x=1/2-3/16` `=>x=8/16-3/16` `=>x=5/16` `—` `|2x-3/7|-1/2=3/4` `=>|2x-3/7|=3/4+1/2` `=>|2x-3/7|=3/4+2/4` `=>|2x-3/7|=5/4` `=>2x-3/7=5/4` hoặc `2x-3/7=-5/4` `=>2x=5/4+3/7` hoặc `2x=-5/4+3/7` `=>2x=35/28+12/28` hoặc `2x=-35/28+12/28` `=>2x=47/28` hoặc `2x=-23/28` `=>x=47/28:2` hoặc `x=-23/28:2` `=>x=47/28. 1/2` hoặc `x=-23/28. 1/2` `=>x=47/56` hoặc `x=-23/56` Vậy `x∈{47/56;-23/56}` `—` `2x+1/3=x-5/2` `=>2x-x=-5/2-1/3` `=>x(2-1)=-15/6-2/6` `=>x=-17/6` Trả lời
a) 3/5 . x – 2/3 = -1/2 b) (1/2 – x) . 2/3 = 1/8
3/5 . x = -1/2 + 2/3 1/2 – x = 1/8 : 2/3
3/5 . x = 1/6 1/2 – x = 3/16
x = 1/6 : 3/5 x = 1/2 -3/16
x = 5/18 x = 5/16
Vậy x = 5/18 Vậy x = 5/16
c) | 2.x – 3/7 | – 1/2 = 3/4
| 2.x – 3/7 | = 3/4 + 1/2
| 2.x – 3/7 | = 5/4
TH1 : 2.x – 3/7 = 5/4 TH2: 2.x – 3/7 = -5/4
2.x = 5/4 + 3/7 2.x = -5/4 + 3/7
2.x = 47/28 2.x = -23/28
x = 47/28 : 2 x = -23/28 : 2
x = 47/56 x = -23/56
Vậy x ∈ { 47/56 ; -23/56 }
d) 2.x +$\frac{1}{3}$ = x – $\frac{5}{2}$
$\frac{6x + 1}{3}$ = $\frac{2x – 5}{2}$
2(6x + 1) = 3(2x – 5)
12x + 2 = 6x – 15
6x – 12x = 15 + 2
-6x = 17
x = 17 : -6
x = $\frac{-17}{6}$
Vậy x = $\frac{-17}{6}$
Đáp án + Giải thích các bước giải:
`3/5x-2/3=-1/2`
`=>3/5x=-1/2+2/3`
`=>3/5x=-3/6+4/6`
`=>3/5x=1/6`
`=>x=1/6:3/5`
`=>x=1/6. 5/3`
`=>x=5/18`
`—`
`(1/2-x).2/3=1/8`
`=>1/2-x=1/8:2/3`
`=>1/2-x=1/8. 3/2`
`=>1/2-x=3/16`
`=>x=1/2-3/16`
`=>x=8/16-3/16`
`=>x=5/16`
`—`
`|2x-3/7|-1/2=3/4`
`=>|2x-3/7|=3/4+1/2`
`=>|2x-3/7|=3/4+2/4`
`=>|2x-3/7|=5/4`
`=>2x-3/7=5/4` hoặc `2x-3/7=-5/4`
`=>2x=5/4+3/7` hoặc `2x=-5/4+3/7`
`=>2x=35/28+12/28` hoặc `2x=-35/28+12/28`
`=>2x=47/28` hoặc `2x=-23/28`
`=>x=47/28:2` hoặc `x=-23/28:2`
`=>x=47/28. 1/2` hoặc `x=-23/28. 1/2`
`=>x=47/56` hoặc `x=-23/56`
Vậy `x∈{47/56;-23/56}`
`—`
`2x+1/3=x-5/2`
`=>2x-x=-5/2-1/3`
`=>x(2-1)=-15/6-2/6`
`=>x=-17/6`