Answer :
[tex]\begin{gathered} 2x-7+19=6x-4x+12 \\ 2x-12=2x+12 \\ 2x-2x-12=12 \\ -12=12 \\ 0=12+12 \\ 0=24 \end{gathered}[/tex]
The last equallity is false! Because 0 IS NOT equal to 24, and thus the initial equation has no solution!!!