a) `| 2x | - | -2,5 | = | -7,5 |`
`2x - 2,5 = 7,5`
`2x = 7,5 + 2,5`
`2x = 10`
`x = 10 : 2`
`x = 5`
b) `| 1 - 3x | = x - 7`
`1 - 3x = x - 7`
`1 + ( -3x ) = x + ( -7 )`
`x + ( -3x ) = 1 + ( -7 )`
`-4x = -6`
`-x = -6 : ( -4 )`
`-x = 1,5`
c) `(1/2x - 3)` `×` `(2/3x + 1/2)` `= 0`
- Vậy: `(1/2x - 3)` `=` `0` hoặc `(2/3x +` `1/2)` `= 0`
`1/2x` `= 0 + 3` `2/3x` `= 0 -` `1/2`
`1/2x` `= 3` `2/3x` `=` `-1/2`
`x = 3` : `1/2` `x =` `-1/2` : `2/3`
`x = 6` `x =` `-3/4`
`=>` `x = 6` hoặc `-3/4`
d) `3/2` `-` `| x - 1 | =` `1/4`
`3/2` `-` `x - 1 =` `1/4`
`3/2` `- x =` `1/4` `+ 1`
`3/2` `- x =` `5/4`
`x =` `3/2` `-` `5/4`
`x =` `1/4`
@ Rin
