Since 6 is positive, it's (x+blank)^2
6/2=3, and (x+3)^2 = x^2+6x+9. We have x^2+6x-2, so we have to add 9 to both sides to get (x+3)^2-2=9, then subtract 9 from both sides to get
(x+3)^2-11=0, or (x+3)^2=11. Square root both sides to get x+3=sqrt(11), and x=sqrt(11)-3, which is approximately 0.32
