The vertex of the parabola is between the shortest line connecting its focus and directrix, so between (0, -4) and y = 4 is the point (0, 0), which is the vertex of the parabola. Also, this parabola faces downward.
The general formula for a parabola that faces downward is y = -4cx^2, where c is the distance from the vertex to either to focus or the parabola. Since c = 4, the equation is y = -16x^2, which is choice A.
Answer:
b. using a sample of size 40
Step-by-step explanation:
edg 2020
5x-3=y 6x-3=y
x=1 x=1
51-3=y 61-3=y
51=5 61=6
5-3=y 6-3=y
2 3
y=2 y=3
