In a sense this is a symmetrical shape because 'x' and 'y' plays the same role - sente for black.
White has two obvious choices to try to make the second eye, namely 'a' and 'b'.
Black connects out with the sente at
.
Next,
takes away whites eye space.
White can't capture the black stones with
.
is met by
.
If white tries
here, again, black plays the sente move at
, and then takes away white's eye space with
.