You are asked to sketch the graphs in this family not by plotting and joining points but by considering the general features of the graph of the rectangular hyperbola xy=1 and of transformations of this graph.

When you make your own pattern of hyperbolae using the equation
x2 a2 - y2 b2 =1

you might like to try making the same transformations as those used in the example Ellipses where the family of equations is given by
x2 a2 + y2 b2 =1.

See the challenge Ellipses here.