Question 734544
At 9 am, Bill begins walking west at 4 miles per hour.
 At 9:30 am Sam begins walking south from the same starting point at 4 miles per hour. 
How far apart are Bill and Sam at 11 am?
:
From the information given, we know that:
 B's walking time = 2 hrs, therefore 2*4 = 8 mi his distance west
 S's walking time = 1.5 hrs, therefore 1.5*4 = 6 mi his distance south
:
The distance between them will the the hypotenuse of a right triagle
with legs of 8 and 6
d = {{{sqrt(8^2+6^2)}}}
d = 10 mi between them