/a, 3/7x+2 3/8=1 2/5 b, x-3/10=7/15.3/5 c 2019x(x-2019/2020)=0 /a, 3 3/7.x+4/7=-4/5 b, 1/3-2/5+3x=3/4 c,(3/7x-7/5).(6-9/10)=0 /a, 2 1/4.x-9 1/4=20 b -1/4-3/4÷x=-11/36 c (2/3x-4/9).(1/2+-3/7÷x)=0 Giúp mik vs ak mik đg cần gấp á

Đáp án:

 

Giải thích các bước giải:

 `a`

`3/7 x + 2 3/8 = 1 2/5`

`3/7x = 39/40`

`x= 91/40`

Vậy `x=91/40`

`b`

`(x-3)/10 = 7/15 * 3/5`

`(x-3)/10 = 7/25`

`(5x-15)/50=14/50`

`5x-15=14`

`5x = 29`

`x=29/5`

Vậy `x=29/5`

`c`

`2019xx ( x-2019/2020)=0`

`x-2019/2020=0`

`x=2019/2020`

`a`

`3 3/7x + 4/7 = -4/5`

`24/7x = -48/35`

`x=-2/5`

`b`

`1/3 - 2/5 + 3x = 3/4

`-1/15 + 3x = 3/4`

`3x = 3/4 + 1/15`

`3x = 49/60`

`x=49/180`

`c`

`(3/7x - 7/5)(6-9/10)=0`

`3/7x - 7/5=0`

`3/7x = 7/5`

`x = 49/15`

`a`

`2 1/4 x - 9 1/4=0`

`9/4x = 37/4`

`x=37/9`

Vậy `x=37/9`

`b`

`-1 1/4 - 3/4 :x =-11/36`

`-3/4x = 29/36`

`x=-39/27`

`c`

`(2/3x -4/9)(1/2 + (-3)/7 :x)=0`

`2/3x-4/9=0` hoặc `1/2 - 3/7: x=0`

`2/3x=4/9` hoặc `3/7:x=1/2`

`x = 2/3` hoặc `x=6/7`

Vậy `x in {2/3;6/7}`