Đáp án + giải thích bước giải :
`a) (3,25 - 2/3x) . (-7/4) = -3`
`-> 3,25 - 2/3x = 12/7`
`-> 2/3x = 43/28`
`-> x= 129/56`
`b) 7/4 - 3/4 : x =7/16`
`-> 3/4 : x = 21/16`
`-> x = 4/7`
`c) 5/2 - 3/4x = 4/5`
`-> 3/4x = 17/10`
`-> x = 34/15`
`d) 3/5x + (-1/2) = -7/10`
`-> 3/5x = -1/5`
`-> x = -1/3`
`e) 4/15 : x + (-1/3) = 5/9`
`-> 4/15 : x= 8/9`
`-> x = 3/10`