Answer:
b
Step-by-step explanation:
Answer:
g(7)= -4
Step-by-step explanation:
10-2(7)
10-14
=-4
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:
120 - 4.5t= 75
t = 10 minutes
Step-by-step explanation:
the equation :
120 - 4.5t= 75
the solution:
-4.5 t = 75-120
-4.5t = -45
t = -45/(-4.5) = 10 minutes