Question 104562
The equation describes a circle center at (0,0) with a radius of 6. 
Any line that goes through the origin is a line of symmetry for this circle, that is, there are an infinite number of symmetric lines for this circle. 
Examples are the x axis, the y axis, and the line shown below, y=1/2x. 

{{{drawing( 300, 300, -10, 10, -10, 10,grid( 1 ),blue(circle( 0, 0, 6 )),line(-10,-5,10,5))}}}