I'll just do the second one. You do the others the same way:


Factor 3 out of the first two terms only. Since 4 is not
divisible by 3 and we have to take out a 3 anyway, we must
divide the 4 by 3 and get a fraction.


Next we complete the square inside the parentheses:
1. Multiply the coefficient of the term in x, which is
,
by
, getting
2. Square this
3. Add and subtract
inside the parentheses:


Group the first three terms in smaller parentheses inside the
larger parentheses:


The inner parentheses trinomial factors like this:


Now we distribute to remove the large parentheses, leaving the smaller
parentheses intact:


Then we complete the fraction work on the end.
Cancel the 3 into the 9 and we have


Get a common denominator of 3 by multiplying the 5 by


And the final vertex form is:


Edwin