Stage: 5 Challenge Level: 
Invistigate symmetry by exchanging $x$ and $y$ in the equation of the graph.
The question itself gives you guidance as to the methods to use.
Graph sketching. Asymptotes. Differentiation of parametric and implicit functions. Parameters. Discussion. Turning points. Symmetry. FP mapping. Families of Graphs. Calculus generally.
Published February 2003.
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