Question 284455
Complete the square in y.
Take (1/2) of the y coefficient and square it.
Add it to both sides. 
{{{x=y^2+6y+4}}}
{{{x+9=(y^2+6y+9)+4}}}
{{{x+9=(y+3)^2+4}}}
{{{x=(y+3)^2-5}}}