document.write( "Question 857260: A boat is being pulled toward a dock by means of a cable attached to a windlass 9 feet above the deck of the boat. The cable is being wound in at a rate of 6 feet per second. How fast is the boat approaching the dock when its horizontal distance to the dock is 12 feet?\r
\n" ); document.write( "\n" ); document.write( "I don't even know how to start this problem, so thank you for your help! \n" ); document.write( "
Algebra.Com's Answer #516471 by josmiceli(19441)\"\" \"About 
You can put this solution on YOUR website!
You have to do a sketch of this
\n" ); document.write( "( if you haven't already )
\n" ); document.write( "In order to understand it. Show the surface
\n" ); document.write( "of the water and the boat 12 ft from the dock
\n" ); document.write( "Show a point where the windlass is on the
\n" ); document.write( "dock 9 ft above the surface of the water.
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\n" ); document.write( "Draw the cable that connects the windlass to the boat.
\n" ); document.write( "Now draw an arrow along this line representing
\n" ); document.write( "the velocity of the cable as it pulls the boat
\n" ); document.write( "( from the boat towards the windlass )
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\n" ); document.write( "Now show horizontal and vertical components
\n" ); document.write( "of this velocity. One component is straight up
\n" ); document.write( "and the other component is horizontal. It is only
\n" ); document.write( "this horizontal component which contributes
\n" ); document.write( "velocity which moves the boat closer to the dock.
\n" ); document.write( "The vertical component contributes nothing.
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\n" ); document.write( "The cable forms a 9 - 12 - c right triangle. Find c.
\n" ); document.write( "\"+c+=+sqrt%28+9%5E2+%2B+12%5E2+%29+\"
\n" ); document.write( "\"+c+=+sqrt%28+81+%2B+144+%29+\"
\n" ); document.write( "\"+c+=+sqrt%28+225+%29+\"
\n" ); document.write( "\"+c+=+15+\"
\n" ); document.write( "-----------------
\n" ); document.write( "This is the length of the cable, and the velocity is
\n" ); document.write( "also along this line. I want to find the horizontal
\n" ); document.write( "component, x, of the velocity. I can say:
\n" ); document.write( "\"+9+%2F+15+=+x+%2F+6+\"
\n" ); document.write( "\"+6%2A9+=+15x+\"
\n" ); document.write( "\"+x+=+18%2F5+\"
\n" ); document.write( "\"+x+=+3.6+\"
\n" ); document.write( "when the boat's horizontal distance to the dock is 12 feet,
\n" ); document.write( "It is approaching the dock at a rate of 3.6 ft/sec.
\n" ); document.write( "Hope it's not confusing.
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