Câu 18. (1,5 điểm) Tìm x, biết: a) x - $\frac{7}{3}$ = $\frac{1}{4}$ b) 2x + $\frac{1}{2}$ = $\frac{1}{3}$

`x - 7/3 = 1/4`

`x = 1/4 + 7/3`

`x = 3/12 + 28/12`

`x = 31/12`

`----`

`2x + 1/2 = 1/3`

`2x = 1/3 - 1/2`

`2x = - 1/6`

`x = - 1/6 : 2`

`x = - 1/2`

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