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

If z² = x² + y²

and

dx/dt = 2

and

dy/dt = 3

Find dz/dt when x=5 and y=12

2. Relevant equations

I used

3. The attempt at a solution

But I resulted in:

2z dz/dt = 2x(dx/dt) + 2y(dy/dt)

Plugged in x,y,dx/dt, and dy/dt to get:

2z (dz/dt) = 2(5)(2) + 2(12)(3)

dz/dt = 80/2z

= 40/z

But the answer is +/- 46/13

Anyone know where I went wrong?

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# Homework Help: Another differentiation problem

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