Question

Suppose a family starts out 50 miles from home at time t = 0. They travel away from home at a constant speed of 45 miles an hour. What's the equation that tells you how far they'll be from home t hours later? (Assume d is distance in miles.) A. d = 45t + 50 B. d = 45t C. d = 50t D. d = 50t + 45

Answer 1

50 miles, t=0 is the start
45 miles each 1 hour

A. d= 45•t+50

Answer 2

At t = 0  d = 50.
At time = 1 hour , d = 50 + 45(1)
At time = 2 hours, d = 50 + 45(2)

So its d = 50 + 45t  or  d = 45t + 50

Choice A is the correct one.