a) `3 1/3 .x + 16 3/4 = -13,25`
`=> 10/3 . x + 67/4 = -53/4`
`=> 10/3 x= -53/4 - 67/4`
`=> 10/3 x= -30`
`=> x= -30 : 10/3`
`=> x= -30 . 3/10`
`=> x= -9`
Vậy `x= -9`
b) `| x- 1/2| + 1/2 = 2,5`
`=> |x- 1/2| + 1/2 = 5/2`
`=>|x- 1/2| = 5/2 - 1/2`
`=> |x-1/2| = 2`
+) `x- 1/2 = 2`
`=> x= 2 + 1/2 `
`=> x= 5/2`
+) `x- 1/2= -2`
`=> x= -2 + 1/2`
`=> x=-3/2`
Vậy `x= 5/2 ` hoặc `x= -3/2`
c) `(4,5 + 3/4 x ) : 8/3 = 9/8`
`=> (9/2 + 3/4 x) = 9/8 . 8/3`
`=> 9/2 + 3/4 x= 3`
`=> 3/4 x = 3- 9/2`
`=> 3/4 x= -3/2`
`=> x= -3/2 : 3/4`
`=> -3/2 . 4/3`
`=> x=-2`
Vậy `x=-2`
