Question

Airplane A takes off and ascends at a rate of 3000 ft/min. At the same time, Airplane B, which is flying at 30,000 ft, begins to descend at a rate of 2500 ft/min.

Let h represent the height off the ground in feet, and let t represent time in minutes.

Which system models this situation?



A.

h = 3000
h = 2500 + 30,000t

B.

h = 30,000 + 3000t
h = 30,000 - 3000t

C.

h = 2500t
h = 30,000 - 3000t

D.

h = 3000t
h = 30,000 - 2500t

Answer 1

@iGreen @Conqueror

Answer 2

3000 feet per minute, what do you think would represent that?

Answer 3

Remember, t represents minutes.

Answer 4

So the equation is going to be?

Answer 5

Would h = 3000t ?

Answer 6

Yes!

And only one option has that.

Answer 7

Would the answer be A ? Would you add 2500 + 30,000t or D ? That is the part that tricks me .

Answer 8

Only one option has h = 3000t, and that's D.

It's not h = 3000, otherwise that means the airplane STAYS at 3000 feet.

Answer 9

Plus for the second one we're subtract 2,500 feet from 30,000 feet, because the second airplane is AT 30,000 feet and is DESCENDING by 2,500 feet per minute.

That gives us 30,000 - 2500t

Answer 10

Oh! I understand. Thanks once again for your help!

Answer 11

No problem!