(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

A boy is standing 50 ft. from the end of a swimming pool when he sees a girl 25 ft. along the end. He can swim 3 ft/s and run 5 ft/s. If he runs x feet, set up an equation for time consumed.

2. Relevant equations

There is a visual aid: A rectangle with length labeled 50 ft and a dot B designating where the boy is, and with a width labeled 25 ft and a dot G designating where the girl is.

3. The attempt at a solution

I know I have to set up a triangle, with my y-axis being the length (where the girl is, making my dy/dt= 3 ft/s) and the x-axis being the width (dx/dt=5 ft/s) Past this, I really don't know. I tried this:

Since he is running x ft, the 50 ft must be losing x, and the 25 ft must be gaining x. So y/x=(25+x)/(50-x) However, I need t in there. If I integrate dy/dt, I will be left with a c that I'm not sure how to get rid of. So yeah, I'm really stumped on this one.

I know it's kinda hard to visualize, so any help at all would be appreciated.

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# Homework Help: Related rates equation problem

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