Answer: The vertex of the parabola (quadratic function) is (-2,-4)
Fourth option: (-2,-4)
Solution:
y=x^2+4x
y=ax^2+bx+c; a=1, b=4, c=0
Vertex: V=(h,k)
h=-b/(2a)
h=-4/(2(1))
h=-4/2
h=-2
y=x^2+4x
k=y=h^2+4h
k=(-2)^2+4(-2)
k=4-8
k=-4
Vertex: V=(h,k)
Vertex: V=( -2, -4)
