A plane was flying an altitude of 30,000 feet when it began the descent toward the airport. The airplane descends at a rate of 850 feet per mintute. A. What is the function rule that describes this situation? B.What is the altitude of the plane after it has descended for 8 minutes? C. Use the function in part A to determine how long it takes for the plane to land if it descends at a continuous rate?

Question

bibby · Answer

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you start off at 30000 and lose 850 for every minute. that's multiplication

anonymous · Answer

Omgosh thank you so much. I don't know why I didn't know this but thank you!

bibby · Answer

I dunno you might not understand the concept, do you want me to go any further?

anonymous · Answer

Correct me if Im wrong, but you got the answer because you're decreasing (subtraction) from 30,000 feet at a rate (multiplication) of 850feet per minute. So you put it together into an equation. 30,000 (the starting point)- 850x (850 f per minute) = y      I hope I understand this correctly /.\

bibby · Answer

yeah, noice

bibby · Answer

I'm used to people not caring enough to understand the problem.. People that just want an answer. Apologies if that seemed hostile.

bibby · Answer

So
A. What is the function rule that describes this situation?
f(x)=30,000-850x
B.What is the altitude of the plane after it has descended for 8 minutes?
plug in f(8)
C. Use the function in part A to determine how long it takes for the plane to land if it descends at a continuous rate?
This means where is f(x) (or y) = to 0?

anonymous · Answer

Oh you didn't come off as hostile at all! In fact this is a huuuge help to me any I really appreciate it! Thank you so much.

bibby · Answer

np brah, it's what we're here for. do you want me to double check any answers?

anonymous · Answer

I don't have any off hand that i'm too worried about, but, do you mind explaining he answer for Part A. I don't understand the f(x) part

bibby · Answer

f(x) is a function of x. it represents a formula we can write out if we have 1 of the 2 variables. so for example:|dw:1414637335676:dw|

the same can be done if we're given a value for f(x) (also known as y)
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