Which function in vertex form is equivalent to f of x is equal to x squared plus 6 x plus 3 ?
A
f of x is equal to open paren x plus 3 close paren squared plus 3B
f of x is equal to open paren x plus 3 close paren squared minus 6C
f of x is equal to open paren x plus 6 close paren squared plus 3D
f of x is equal to open paren x plus 6 close paren squared minus 6