Answer:
y = -1/10x^2 +2.5
Step-by-step explanation:
The distance from focus to directrix is twice the distance from focus to vertex. The focus-directrix distance is the difference in y-values:
-1 -4 = -5
So, the distance from focus to vertex is p = -5/2 = -2.5. This places the focus 2.5 units below the vertex. Then the vertex is at (h, k) = (0, -1) +(0, 2.5) = (0, 1.5).
The scale factor of the parabola is 1/(4p) = 1/(4(-2.5)) = -1/10. Then the equation of the parabola is ...
y = (1/(4p))(x -h) +k
y = -1/10x^2 +2.5
_____
You can check the graph by making sure the focus and directrix are the same distance from the parabola everywhere. Of course, if the vertex is halfway between focus and directrix, the distances are the same there. Another point that is usually easy to check is the point on the parabola that is even with the focus. It should be as far from the focus as it is from the directrix. In this parabola, the focus is 5 units from the directrix, and we see the points on the parabola at y=-1 are 5 units from the focus.
12:45Answer:
Part A: 9 hours 45 minutes
Part B: $126.1575
Step-by-step explanation:
Part A,
From 7:45 to 12:15 is 4 hours and 30 minutes
From 12:45 which he clocked back in to 6:00 is 5 hours and 15 minutes.
4 hours and 30 minutes plus 5 hours and 15 minutes = 9 hours and 45 minutes.
Part B, 9 hours and 45 minutes can be represented as 9.45
And since he gets 15.35 "per" hour shows we can multiply.
15.35 x 9.45 = 126.1575
Therefor he earned 126.15.
Answer:
Step-by-step explanation:
distance flown in 5.4 hours = 245.6 miles
distance flown in 1 hour = 245.6/5.4
= 45.481 miles
Hope this helps
plz mark as brainliest!!!!!
I think the answer is B not sure though