\begin{frame}
  \frametitle{Implicit Differentiation}
  
  Consider the equation:
  \begin{talign}
    x^2 + y^2 = 25
  \end{talign}
  \pause
  This equation describes a circle:
  \begin{center}
  \scalebox{1}{
  \begin{tikzpicture}[default,baseline=1cm,scale=.3]
    \diagram{-6}{6}{-6}{6}{1}
    \diagramannotatez
    \begin{scope}[ultra thick]
      \draw[cgreen,ultra thick] (0,0) circle (5);
    \end{scope}
  \end{tikzpicture}
  }
  \end{center}
  \pause\medskip
  
  This is not a function and we cannot write it as:
  \begin{talign}
    y = \ldots \mpause[1]{ \quad\text{\textcolor{gray}{unless we split the circle in upper and lower half}} }
  \end{talign} 
  \pause\pause 
  How to compute the slope of points on this curve?
  \vspace{10cm}
\end{frame}