4.4 Circles and ellipses

Circle cx="50" cy="50" r="40" and circle cx="50" cx="50" r="2"
...
Ellipse cx="50" cy="50" rx="40" ry="20" and circle cx="50" cx="50" r="2"
...
In both circles and ellipses, if the cx or cy is omitted, it is presumed to be zero.