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

2 cars start from the same point. Car A travels a constant 50 mph due west. Car B travels a constant 27 mph due south. After 3 hours, how fast is the distance changing between them?

2. Relevant equations

3. The attempt at a solution

I saw this problem online have been stumped trying to solve it. To start I drew a right triangle according to the problem. I have car A travelling west and car B travelling south. I labeled the hypotenuse side C. I tried to write an equation relating the three sides and (using phythagoras) I said that:

[tex]C=\sqrt{A^2+B^2}[/tex]

My thought was to take the derivative of this equation and then find it's value at 3 hours. I don't think this is correct because I would be taking the derivative with respect to time (I think) and I am not sure how to handle both A and B.

I would like a small hint in the correct direction. I am anxious to solve this one myself, if possible please hold off on presenting the solution.

Thanks for taking the time to read and help.

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# Homework Help: How fast is the distance changing? (FODE, I think)

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