Nazima is fly fishing in a stream. The tip of her fishing rod is 1.8 m above the surface of the water and the fly at the end of the string rests on the water 3.6 m away and 2.4 m from a point directly under the tip of the rod. Assuming that her string (from the tip of her rod to the fly) is taut, how much string does she have out? If she pulls in the string at the rate of 5 cm per second, what will be the horizontal distance of the fly from her after 12 seconds?

Explanation

Let AB be the height of the tip of the fishing rod from the water surface.


Let BC be the horizontal distance of the fly from the tip of the fishing rod.
Then, AC is the length of the string.


`∴ AC^2 =AB^2 +BC ^2`
[ By Pythagoras theorem ]
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