Determine this equation in standard form

Question

Where the x intercepts is -2 +/- √5, containing the point (-4,5)... the answer is supposed to be -5x^2-20x+5 but I keep getting the wrong answer.

Answer 1

x = -2 + sqr5 and x = -2 -sqr5

a(x - (-2-sqr5))(x-(-2+sqr5)

= a(x+2+sqr5)(x +2-sqr5)

=a(x+2)^2 -5)

=a(x^2 +4x -1)

=5 = a(16-16-1)=-a

a =-5

f(x)= -5x^2 -20x+5