First, distribute the exponent: (x-1)² = x² – 2x + 1.  Then set up this equation:
x² – 2x + 1 (-2x)= 2x + 1 (-2x)
x² – 4x + 1 (-1) = 1 (-1)
x² – 4x = 0
Now, factor:
x (x-4) = 0
x = 0, x-4 = 0
So, x= 4 (D) because the problem specified that x cannot be 0.
 

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