x - [( x - 7 ) + (x - 14 + 8 )] = 2x - 14
x - [ x - 7 + x - 14 + 8 ] = 2x - 14
x - x + 7 - x + 14 - 8 = 2x - 14
x - x - x - 2x = -14 - 7 - 14 + 8
-3x = -27
=> x = 9
Vậy...
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x-[(x-7)+(x-14+8)]=2x-14
x-[x-7+x-14+8]=2x-14
x-x+7-x+14-8=2x-14
x-x-x-2x=-14-7-14+8
-3x=-27
=> x=9
Vậy x=9
x - [( x - 7 ) + (x - 14 + 8 )] = 2x - 14
x - [ x - 7 + x - 14 + 8 ] = 2x - 14
x - x + 7 - x + 14 - 8 = 2x - 14
x - x - x - 2x = -14 - 7 - 14 + 8
-3x = -27
=> x = 9