Question

tìm X biết 

0,9:(\(\dfrac{2}{5}\)-x)=\(\dfrac{7}{5}\)

Answer 1

`0,9 : (2/5 - x) = 7/5`

`2/5 - x = 0,9 : 7/5`

`2/5 - x = 9/10 : 7/5`

`2/5 - x = 9/10 xx 5/7`

`2/5 - x = 9/14`

`x = 2/5 - 9/14`

`x = -17/70`

 

`#BaoL i n h`

Answer 2

`0,9 : (2/5 - x) = 7/5`

`2/5 - x = 0,9 : 7/5`

`2/5 - x = 9/10 xx 5/7`

`2/5 - x = 9/14`

`x = 2/5 - 9/14`

`x = -17/70`

Answer 3

0,9 : ( 2/5 - x ) = 7/5 

2/5 - x = 0,9 : 7/5 

2/5 - x = 9/10 : 5/7 

2/5 - x = 9/10 x 5/7 

2/5 - x = 9/14

 x = 2/5 - 9/14 

 x = -17/70