Tìm x: a) 1/2 . x – 2/3 = -5/9 b) |x-1|=5

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1. `a)1/2x-2/3=(-5/9)`
   `=>1/2x=(-5/9)+2/3`
   `=>1/2x=1/9`
   `=>x=1/9:1/2=2/9`
   `b)|x-1|=5`
   `TH_1:|x-1|=5`
   `=>x-1=5`
   `=>x=5+1=6`
   `TH_2:|x-1|=5`
   `=>x-1=(-5)`
   `=>x=(-5)+1`
   `=>x=(-4)`
   Vậy `x=(6;-4)`

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2. Đáp án:

   `a)1/2*x-2/3=-5/9`

   `\qquad 1/2*x=-5/9+2/3`

   `\qquad 1/2*x=-5/9+6/9`

   `\qquad 1/2*x=1/9`

   `\qquad x=2/9`

   Vậy `x=2/9`

   `b)|x-1|=5`

   `=>` \(\left[ \begin{array}{l}x-1=5\\x-1=-5\end{array} \right.\) 

   `=>` \(\left[ \begin{array}{l}x=6\\x=-4\end{array} \right.\) 

   Vậy `x=6` hoặc `x=-4`.

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