Question 832775
{{{3n-6+n=2(2n-6)}}}, Given.


3n-6+n=2(2n-6)
{{{4n-6=2(2n-6)}}}, Combined like-terms on the left member
{{{4n-6=4n-12}}}, Distributive Property
{{{4n=4n-6}}}, Using just one step, added 6 to both members
NO SOLUTION!
If you try to isolate terms of n on either side, you cannot.  This equation has no solution.  The equation is false!
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Subtracting 4n from both sides will be of no help, because you would obtain {{{0=-6}}}, a false statement.