Problem:

The altitude of an airplane descending to an airport is represented by the equation shown below, where y represents the altitude, in feet, of the airplane and x represents the number of minutes since landing began.

y = - 125x + 40,000

Part A:

What is the altitude of the airplane after 5 minutes? after 30 minutes? Show your work then write your answers as ordered pairs (x, y).

Part B:

Create a table for the values when x = 0, 5, 8, 10, 30.

Part C:

Which ordered pair (from the table in part B) represents the initial value? What does the initial value represent in this problem? (1-2 sentences)

Part D:

What is the rate of change in this equation? What does the rate of change represent in this problem? (1-2 sentences)

Question

Derek Hicks

Mathematics

2 November, 11:06

Problem:

The altitude of an airplane descending to an airport is represented by the equation shown below, where y represents the altitude, in feet, of the airplane and x represents the number of minutes since landing began.

y = - 125x + 40,000

Part A:

What is the altitude of the airplane after 5 minutes? after 30 minutes? Show your work then write your answers as ordered pairs (x, y).

Part B:

Create a table for the values when x = 0, 5, 8, 10, 30.

Part C:

Which ordered pair (from the table in part B) represents the initial value? What does the initial value represent in this problem? (1-2 sentences)

Part D:

What is the rate of change in this equation? What does the rate of change represent in this problem? (1-2 sentences)

+2

Answers (1)

Know the Answer?

Marley · Answer 1

A) replace x in the equation with 5 and 30 and solve for y:

y = - 125 (5) + 40,000 = - 625 + 40,000 = 39,375 feet after 5 minutes

y = - 125 (30) + 40,000 = - 3750 + 40000 = 36,250 feet after 30 minutes.

B)

x = 0 y = 40,000

x = 5 y = 39,375

x = 8 y = 39,000

x = 10 y = 38,750

x = 30 y = 36,250

C) Initial value is when x is 0, which is 40,000 ft. this is the altitude of the plane before it started descending.

D) The rate of change is the number being multiplied by x, which is - 125.

This means the plane is descending 125 feet per minute.