Answer:
9
Step-by-step explanation:
you want the trinomial (x*x - 6x + __ ) to be written as a binomial squared.
So we would need to realize that the constant would be equal to (-6/2)^2 =(-3)^2 = 9
We have completed the square.
f(x) = 4*( x - 3)^2 + 20 is now in Vertex Form
