Thread: Precalc word problem

Originally Posted by Intrusion

Jason leaves Detroit at 2:00 PM and drives at a constant speed west along I-96. He passes Ann Arbor, 40 miles from Detroit, at 2:50 PM.

Find an equation to express the distance traveled in terms of the time elapsed, then graph it.

How would I get the equation?

Thanks for all help!

distance = (time)(velocity), and you know it took him 50 minutes to travel 40 miles, and you also know that he traveled and constant speed, so...

can you see the equation from this?

Originally Posted by emathinstruction

distance = (time)(velocity), and you know it took him 50 minutes to travel 40 miles, and you also know that he traveled and constant speed, so...

can you see the equation from this?

Right, 40 = (50/60)S --> S = 48 mph...so equation would be D = 48T? And graph that? Am I missing a step?

that looks good to me

Originally Posted by Intrusion

Right, 40 = (50/60)S --> S = 48 mph...so equation would be D = 48T? And graph that? Am I missing a step?

Assuming that "T is the time since 2 PM in hours and D is the distance from Detroit in miles", which should be stated, yes, that is correct. The graph, of course, is a straight line.