Question

Complete the square and write in function form f(x)=x^2+5x+3

Answer 1

F(x) = x^2 +5x + 3

     = (x + 2.5)^2 - 6.25 + 3

     = (x + 2.5)^2 - 3.25

That is vertex form. I am not sure what you mean by function form