You do [tex] \frac{sin(y)}{2} = \frac{sin30}{what you got for x} [/tex] and then cross multiply and simply it.
[tex](what you got for x)sin(y)=2sin30[/tex]
divide (what you got for x) to both side
you should get something like [tex]sin(y)= \frac{2sin30}{what you got for x} [/tex]
then just use a calculator and do [tex] sin^{-1} ( \frac{2sin30}{what you got for x} )[/tex]