document.write( "Question 593418: You are in a boat a miles from the nearest point on the coast (see figure). You are to go to a point Q, which is b miles down the coast and 1 mile inland. You can row at 4 miles per hour and walk at 5 miles per hour. If a = 2, and b = 4, toward what point on the coast should you row in order to reach Q in the least time? (Round your answer to three decimal places.) \n" ); document.write( "
Algebra.Com's Answer #376433 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
Rewrite the problem:
\n" ); document.write( "You are in a boat 2 miles from the nearest point on the coast (see figure, it would be nice!).
\n" ); document.write( "You are to go to a point Q, which is 4 miles down the coast and 1 mile inland.
\n" ); document.write( " You can row at 4 miles per hour and walk at 5 miles per hour.
\n" ); document.write( "Toward what point on the coast should you row in order to reach Q in the least time?
\n" ); document.write( ":
\n" ); document.write( "Let x = distance from the coastal point nearest the boat, to where he should land the boat
\n" ); document.write( "then
\n" ); document.write( "(4-x) = distance from the landing point to the coastal point nearest Q
\n" ); document.write( ":
\n" ); document.write( "The distance rowed and and walked will be the hypotenuse of two triangles
\n" ); document.write( "write a time equation; time = dist/speed
\n" ); document.write( ":
\n" ); document.write( "total time = rowing time + walking time
\n" ); document.write( "t(x) = \"%28sqrt%282%5E2%2Bx%5E2%29%29%2F4\" + \"%28sqrt%281%5E2%2B%284-x%29%5E2%29%29%2F5\"
\n" ); document.write( ":
\n" ); document.write( "t(x) = \"%28sqrt%284%2Bx%5E2%29%29%2F4\" + \"%28sqrt%281%2B%2816-8x%2Bx%5E2%29%29%29%2F5\"
\n" ); document.write( ":
\n" ); document.write( "t(x) = \"%28sqrt%284%2Bx%5E2%29%29%2F4\" + \"%28sqrt%28x%5E2-8x%2B17%29%29%2F5\"
\n" ); document.write( ":
\n" ); document.write( "t(x) = \"%285%28sqrt%284%2Bx%5E2%29%29+%2B+4%28sqrt%28x%5E2-8x%2B17%29%29%29%2F20\"
\n" ); document.write( "The graph, time on the y axis
\n" ); document.write( "
\n" ); document.write( "Minimum time, landing point: x = 2 mi from the coastal point nearest the boat,
\n" ); document.write( ":
\n" ); document.write( "Sorry I sent this prematurely by mistake. C
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