What is the Derivative of a Cubic Function with a Given Value of x?

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Homework Statement



If y = x³ + 2x
and
dx/dt = 5,
find
dy/dt when x = 2.


The Attempt at a Solution



I'm not really sure how to solve this problem at all. It's the first I've seen like this so I don't know what approach I should take.
 
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Use the chain rule in the form:
[tex] \frac{dy}{dt}=\frac{dy}{dx}\frac{dx}{dt}[/tex]