Answer:
Plane 1
[tex]y_{1} = 38250\,ft - \left(750\,\frac{ft}{min}\right)\cdot t[/tex]
Plane 2
[tex]y_{2} = 9400\,ft + \left(550\,\frac{ft}{min}\right)\cdot t[/tex]
Step-by-step explanation:
As each plane is travelling at constant speed, each equation can be modelled after this expression:
[tex]y = y_{o} + \dot y \cdot t[/tex]
Where:
[tex]y_{o}[/tex] - Intial elevation of the airplane, measured in feet.
[tex]\dot y[/tex] - Climbing/Descending rate of the airplane, measured in feet per minute. (Positive - Climbing, Negative - Descending)
[tex]t[/tex] - Time, measured in minutes.
Equations are described below:
Plane 1
[tex]y_{1} = 38250\,ft - \left(750\,\frac{ft}{min}\right)\cdot t[/tex]
Plane 2
[tex]y_{2} = 9400\,ft + \left(550\,\frac{ft}{min}\right)\cdot t[/tex]