First expand both sides of the equation via distributive property.
3x-6+7=3x-1
Combine like terms
3x+1=3x-1
Add 1 to both side to cancel out the "1" on the right
3x+2=3x
Subtract 3x from both sides
3x+2-3x=3x-3x
2=0
Does 2 equal zero? No. Therefore, the answer doesn't exist.