Question

The Chang family is on their way home from a cross-country road trip. During the trip, the function D(t) = 2,280 - 60t can be used to
represent their distance, in miles, from home after t hours of driving. What is the value of t when D(t) = 1,200? What does that value
represent?
A. t = 20; the Chang family has been driving for 20 hours
B. t = 20; the Chang family has 20 hours more to drive to get home
c. t = 18; the Chang family has been driving for 18 hours
D. t = 18; the Chang family has 18 hours more to drive to get home

Answer 1

Answer:

c. t = 18; the Chang family has been driving for 18 hours

Step-by-step explanation:

Given:

D(t) = 2,280 - 60t

Find t when D(t) = 1,200

D(t) = 2,280 - 60t

1200 = 2280 - 60t

Subtract 2280 from both sides of the equation

1200 - 2,280 = 2280 - 60t - 2,280

- 1080 = - 60t

Divide both sides by -60

- 1080 / -60 = - 60t / -60

18 = t

t = 18

This means the Chang family has been driving for 18 hours

c. t = 18; the Chang family has been driving for 18 hours