Answer:
The step 4 is not what he should have done. But the wrong is step 5, because if he added -2x both sides, it would give the following equation:
[tex]x-12=-4x+6[/tex]
and not [tex]x-12=6[/tex]
Note that in step 4 he should have added 2x and not -2x to both sides, but we still have the equality. The problem is that step 5 is totally wrong.
I don't know what answer is expected to this question, but I would mark step 5, because this is mathematically wrong.
Solving the equation
[tex]3(x-4)=-4-2(x-5)[/tex]
Using distribution
[tex]3x-12=-4-2x+10\\3x-12=-2+6[/tex]
Add [tex]2x[/tex] both sides
[tex]3x-12+2x=-2x+6+2x[/tex]
[tex]5x-12=6[/tex]
Add 12 both sides
[tex]5x-12+12=6+12\\5x=18[/tex]
Divide both sides by 5
[tex]$x=\frac{18}{5} $[/tex]
