<PRE><B>Question 274698</B>
Two ships leave port at the same time. One sails south at 15mph and the other sails east at 2o mph. Find a function that models the distance (D) between the ships in terms of the time (T) in hours elasped since thier departure. 
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Draw the picture.
East distance = 20t
South distance = 15t
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Using Pythagoras:
D^2 = (20t)^2 + (15t)^2
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D^2 = 400t^2 + 225t^2
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D^2 = 625t^2
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D = 25t
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Cheers,
Stan H.</PRE>