Question

The table below represents the distance of an airplane from its destination as a function of time:

Time
(hours)
x Distance
(miles)
y
0 2,700
1 2,160
2 1,620
3 1,080
4 540


Part A: What is the y-intercept of the function, and what does this tell you about the airplane? (4 points)

Part B: Calculate the average rate of change of the function represented by the table between x = 1 to x = 4 hours, and tell what the average rate represents. (4 points)

Part C: What would be the domain of the function if the airplane continued to travel at this rate until it reached its destination? (2 points)

Answer 1

A: Y=95x+665. The y-intercept is 665

B: The average rate of change is -95

C: y=0, x=7. So the domain is (0,7)

make sure you write it on your own.

Answer 2

Part A) the Y intercept is where x = 0.

Y intercept = 2,700. This means the plan is 2700 miles away from it's destination

Part B) at X1 y = 2160

X4 y = 540

rate of change = y2-y1 over x2-x1 using X4 and X1

rate of change = 540 -2160 / 4-1 = -1620/3 = -540

for every 1 hour traveled the plane is getting 540 miles closer to it's destination

Part C) the domain would be all the X numbers

so at hour 4 it is 540, the rate of change is also 540 so at hour 5 it would be at it's destination so the domain would be (0,1,2,3,4,5)