Check request: Implicit Differentiation

DollarBill
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Homework Statement


Find the value of dy/dx at x=2 when

x2+xy=5

The Attempt at a Solution



To find y:
22+2y=5
y=1/2

To find dy/dx:
2x(dx/dx)+x(dy/dx)+y(dx/dx)=0

2x+x(dy/dx)+y=0

(dy/dx)=(-2x-y) / x

Plug in y and x:
dy/dx=-2(2)-(1/2) / 2

dy/dx=-9/4 when x=2
 
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Correct.
 
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