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LMTSML
Jan 1, 2008, 10:56 AM
I have this related rates problem, but I keep getting a negative number for dx/dt... heres the problem.. HELP!

A person is hanging a banner along the side of a wall by a rope tied to the top of the bar. The banner is 5 meters long. If the person pulls the banner up at a rate of 0.5 meters per second. How fast is the bottom of the banner sliding across the ground when it is 3.0 meters from the wall?

I keep getting that dx/dt is -2/3 meters per second.. how can that be?
HELP! PLEASE! Thank you!

galactus
Jan 1, 2008, 11:01 AM
That is correct. Good work. The reason it is negative is because the banner is sliding toward the wall. If it were going away it would be positive.

mustapha
Jan 3, 2008, 01:56 AM
integrate 2^x+4y-2x