CPM Homework Help : CALC Problem 8-82

Multiple Choice: If $x^{2} − 2xy = 8$ , then when $x = 2$ , $\frac{dy}{dx}=$

$−\frac{1}{2}$

$\frac { 1 } { 2 }$

$\frac { 3 } { 2 }$

$−\frac{3}{2}$

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Hint:

the derivative might have both $x$ and $y$ variables in it.
So be prepared for the final step: you will need to know what y-variable corresponds with $x = 2$ on the given graph.