Question

A plane at 3,800 feet is descending at a rate of 120 feet per minute, and a plane at 520 feet is climbing at a rate of 40 feet per minute. In how many minutes will they be at the same altitude? Write a system of equations. Then graph the system to determine the solution.

Answer 1

so the basic formula for this d = rt

where d is the distance , r is the speed and t is time

 

3800 – 120t = 520 + 40t ( this is the altitude of each plane are equal)

Solve for t

T = 20.5 min time it takes for the planes to be at the same altitude

 

3800 – 120(20.5) = 1340 ft