Answer:
6 minutes
Step-by-step explanation:
'a' in the formula represents altitude in feet. You are told the altitude is 21000 feet, so put that into the formula:
21000 = 3400t +600
You can solve this for t:
20400 = 3400t . . . . . subtract 600 from both sides
6 = t . . . . . . . . . . . . . . . divide both sides by 3400
The problem statement tells you that t represents minutes after lift off, so this solution means the altitude is 21000 feet 6 minutes after lift off.
The question is asking for the number of minutes after lift off that the plane reaches an altitude of 21000 feet, so this answers the question directly:
The plane is at an altitude of 21000 feet 6 minutes after lift off.
It goes by 3s so I think its 1.2
the answer is d thats what im choosing because i recall doing a similar problem to this
Answer:
[y]
-16
-12
0
12
16
Step-by-step explanation:
Put the x value in the equation to find your answer
Given that
, we have
, so that

Take the derivative and find the critical points of
:

Take the second derivative and evaluate it at the critical point:

Since
is positive for all
, the critical point is a minimum.
At the critical point, we get the minimum value
.