3x^2 + 4x + 1 divide by 3
x^2 + 4/3 x + 1/3 complete the square
(x+ 4/6)^2 -16/36 +1/3 =
(x + 4/6)^2 - 1/9 now put the '3' back in
3 (x+4/6)^2 -1/3 now you can see a h and k
We complete the square.
\(3x^2+4x+1\\ =3(x^2+\frac{4}{3}x+\frac{1}{3})\\ =3(x+\frac{2}{3})^2-\frac{1}{3}\)
So a=3, h=2/3, and k=-1/3.