Horizontal Tangent - Implicit Differentiation
a curve in the plane is given by the following equation
A) Find an expression for dy/dx using implicit differentiation
B) Find the four points on the curve where the tangent line is horizontal
Ok I know how to solve for the derivative. I got
dy/dx = (4x^3-4xy)/(2x^2+6y)
However Im not quite sure how to solve when the tangent is horizontal. I that the tangent is horizontal when the derivative equals 0. However I don't know how solve for this when it is an implicit derivative.