a ) 3x - ( - 2 ) = 1
3x = 1+(-2)
3x = -1
x = - 1 : 3
x = $\frac{-1}{3}$
b) -( 2x + 24 ) + 211 = -123
- ( 2x - 24 ) + 211 = -123
2x - 24 = 123 - 211
2x - 24 = -334
2x = -334 + 24
2x = -310
x = -310 : -2
x = 155
c) 125 - (125 - x ) = 0
125 - x = 125 - 0
125 - x = 125
x = 125 - 125
x = 0
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