Question 575446
<font face="Times New Roman" size="+2">


If *[tex \Large d\ =\ rt], then *[tex \Large r\ =\ \frac{d}{t}].  Let *[tex \Large r_s] represent the speed of the plane in still air and let *[tex \Large r_w] represent the speed of the wind.  When the plane is flying with the wind, the true speed of the plane is *[tex \Large r_s\ +\ r_w], and against the wind it is *[tex \Large r_s\ -\ r_w].


With the wind he goes 300 miles in 2 hours, so his true speed is 150.  Against the wind he goes 270 miles in 2 hours, so his true speed is 135.  So:


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ r_s\ +\ r_w\ =\ 150]


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ r_s\ -\ r_w\ =\ 135]


Solve the 2X2 system for *[tex \Large r_s] and *[tex \Large r_w]


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>