In polar coordinates the equation r a is a circle of radius

In polar coordinates, the equation r = a is a circle of radius a in the xy-plane. Show that in hyperbolic coordinates, the equation R = a is the equation of a hyperbola in the xy-plane.

Solution

there is no hyperbolic co ordinates in two dimentional system

we have only carteian and polar co ordinates in 2 dimentional.

so question is no clear