Multiply out the "a times the squared coefficient" part on the left-hand side (remember, in this one a = 1 so that does nothing), and convert the right-hand side to squared form. (This is where you use that sign you kept track of earlier, putting that sign in the middle of the squared expression.)
y-4+(9)=(x+3)^2
Simplify - combine like terms.
y+5=(x+3)^2
Move the constant term from the right back to the left.
y=(x+3)^2 - 5
Write in vertex form y=(a(x-h)^2) + k. In other words, if the squared term is x+h write it as x-(-h). If the k term is negative, write it as + (-k).
y=(x-(-3))^2 + (-5)
Now the values for h and k are clear.I hope that this is the answer that you were looking for and it has helped you.