c) `1/2 x - 3/4 = 14/9 . 3/7`
`1/2 x - 3/4 = 2/3`
`1/2 x = 2/3 + 3/4`
`1/2 x= 17/12`
`x= 17/12 : 1/2`
`x= 17/12 .2`
`x=17/6`
Vậy `x= 17/6`
f) `( 4,5 -2x ) . (-1 4/7) = 11/14`
` 4,5 -2x = 11/14 : (-1 4/7)`
`4,5 -2x = 11/14 :( -11/7)`
` 4,5 - 2x = 11/14 . (-7/11)`
`4,5 - 2x= -1/2`
`4,5 - 2x = -0,5`
`2x= 4,5 + 0,5`
`2x = 5`
`x= 5/2`
Vậy `x= 5/2`
