Now we need to do some algebra to isolate . First, we move all of the terms that do not
contain to the right side of the equals sign.x^2 + 2y = 4 − 2xyNext, we factor out : (x^2 + 2y) = 4 − 2xy.
Finally, we divide through by (x^2 + 2y) to isolate .
(b) Find .
We need to use the Quotient Rule and implicit differentiation.
Next, substitute into the derivative.
There is no need to simplify this.
(c) Find the equation of the tangent lines at each of the two points on the curve whose x-
coordinate is 1.