This is not enough info to determine the length of teds pencil
Given:
The focus of the parabola is at (6,-4).
Directrix at y=-7.
To find:
The equation of the parabola.
Solution:
The general equation of a parabola is:
...(i)
Where, (h,k) is vertex, (h,k+p) is the focus and y=k-p is the directrix.
The focus of the parabola is at (6,-4).

On comparing both sides, we get

...(ii)
Directrix at y=-7. So,
...(iii)
Adding (ii) and (iii), we get



Putting
in (ii), we get



Putting
in (i), we get


Therefore, the equation of the parabola is
.
Answer:
I'd say half
Step-by-step explanation:
160/4 = 40 mph so that would be the answer simply divide