I made a typo, sorry. If I rearrange it to read 9x^+18x+9y^-12y=131 I know I need to factor out a number before completing the square on both sides, but if I factor out a 3 it's got me confused.
Example: 4x^+12x+4y^+24y-99=0 move the 99 and factor out a 4, then complete the square both sides
4(x+3/2)^+4(y+3)^=144 divide both sides by 4
(-3/2,-3) radius 6
The first example just isn't working out for me.