[tex]3x - 3(x + 1) = 3 \\ = > - 3(x + 1) = 3 - 3x \\ = > - 3(x + 1) = - 3(1 + x) \\ [/tex]
Hence, 
[tex] x [/tex] is cutting each other in this equation. 
So, [tex] x [/tex] can be of any value.i.e.,infinite. 
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