What is the derivative of xy = -4

Question

at point (-1,4)?? 

Answer 1

The Function is xy = -4

Point (-1,4)

Differentiate the function with respect to x.

x*y' + y = 0     (Using Rule of Differentiation (uv)' = uv'+vu')

y ' = -y / x

y' = -4 / (-1)

y' = 4

Therefore Derivative of xy = -4 at Point (-1,4) is y' = 4.