1. The problem statement, all variables and given/known data Suppose we have an equation, ex + xy + x2 = 5 Find dy/dx 2. Relevant equations Now I know all the linear differentiation stuff like product rule, chain rule etc. Also I know partial differentiation is differentiating one variable and keeping other one constant. 3. The attempt at a solution By my method I can evaluate like, Differentiating both sides ex + y + xdy/dx + 2x = 0 and then rearrange to get dy/dx. But my question is When f(x,y) = 0 How dy/dx = -δx/δy ? This is really a fast method as we don't have to rearrange terms.