Đáp án `+` Giải thích các bước giải:

`a)`

`\frac{x}{3} - \frac{5}{2} = \frac{7}{6}`

`\frac{x}{3} = \frac{7}{6} + \frac{5}{2}`

`\frac{x}{3} = \frac{11}{3}`

`=> x . 3 = 3 . 11`

`x . 3 = 33`

`x = 33 : 3`

`x = 11`

Vậy `x = 11`

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`x + \frac{1}{2} = \frac{25}{12} - \frac{5}{6}`

`x + \frac{1}{2} = \frac{25}{12} - \frac{10}{12}`

`x + \frac{1}{2} = \frac{15}{12}`

`x + \frac{1}{2} = \frac{5}{4}`

`x = \frac{5}{4} - \frac{1}{2}`

`x = \frac{5}{4} - \frac{2}{4}`

`x = \frac{3}{4}`

Vậy `x = \frac{3}{4}`

`b)`

`x - \frac{2}{3} = -(-\frac{1}{3} - \frac{3}{4})`

`x - \frac{2}{3} = \frac{1}{3} + \frac{3}{4}`

`x - \frac{2}{3} =frac{13}{12}`

`x = \frac{2}{3} + \frac{13}{12}`

`x = \frac{8}{12} + \frac{13}{12}`

`x = \frac{21}{12}`

`x = \frac{7}{4}`

Vậy `x = \frac{7}{4}`