Plane what time will they be at the same altitude.

Question

an air traffic controller is tracking two planes. To start, Plane A is at an altitude of 2651

 feet and Plane B is just taking off. Plane A is gaining altitude at 25.5

 feet per second and Plane B is gaining altitude at 85.75

 feet per second.

Answer 1

Hi Everette,

Set up equations for distance (altitude) of both planes. I use d instead of a since we already have a plane A. For plane A, it starts at 2651 ft., so we have to include that. Plane b starts at 0, so we don't include that. Plane A gains altitude at 25.5 ft./sec., so we express that as 25.5*t, where t is the time point we are looking for where the planes meet. Plane B gains altitude at 85.75 feet per second, so we express as 85.75*t.

D(A)=2651 + 25.5t

D(B)=85.75t

Now, we want them to meet, which means we want them to be equal to each other:

85.75t=2651 + 25.5t

Subtract 25.5t on both sides:

60.25t=2651

Divide both sides by 60.25:

t=44 seconds

I hope this helps.

Answer 2

2651 + 25.5s= 85.75s

60.25s = 2651

s = 2651/60.25 = 44 seconds