Question 536637
<font face="Times New Roman" size="+2">


Distance equals rate times time.  You are given a rate of 72 mph and a time of *[tex \Large x] hours.  So the distance traveled in *[tex \Large x] hour at 72 mph is *[tex \Large 72x] miles.  But since he is starting at 270 miles from home going toward home the distance from home is 270 miles minus the distance he has traveled in *[tex \Large x] hours, hence:


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ D(x)\ =\ 270\ -\ 72x]


John
*[tex \LARGE e^{i\pi} + 1 = 0]
My calculator said it, I believe it, that settles it
<div style="text-align:center"><a href="http://outcampaign.org/" target="_blank"><img src="http://cdn.cloudfiles.mosso.com/c116811/scarlet_A.png" border="0" alt="The Out Campaign: Scarlet Letter of Atheism" width="143" height="122" /></a></div>
</font>