Which function in vertex form is equivalent to f (x) = x2 + 6x + 3?

f (x) = (x + 3) 2 + 3

f (x) = (x + 3) 2 - 6

f (x) = (x + 6) 2 + 3

f (x) = (x + 6) 2 - 6

Complete the square

move the 3 aside and work in parenthasees

f (x) = (x^2+6x) + 3

take 1/2 of 6 and square it (6/2=3, 3^2=9)

add 9 and - 9 inside

f (x) = (x^2+6x+9-9) + 3

factor perfect square

f (x) = ((x+3) ^2-9) + 3

get rid of parenthases

f (x) = (x+3) ^2-9+3

f (x) = (x+3) ^2-6

2nd choice