Answer: D is the correct answer
If f(x)=x^2-8x-20 then
dy/dx=2x-8 and d2y/dx2=2
A) Since acceleration is a constant positive the parabola opens upward.
B) Since acceleration is a constant positive the parabola will have a vertex at an absolute minimum
C) The vertex will occur when dy/dx=0, 2x-8=0, 2x=8, x=4
So the axis of symmetry is the vertical line x=4.
The vertex is y(4)=-36, corresponding to the vertex point (4,-36)
The y-intercept occurs when x=0, y(0)=-20, so the y-intercept is the point (0,-20)
Answer:
x= -19/8
Step-by-step explanation:
