How can I solve this Trigonometry equation in RxR?

[Andrax]

Homework Statement

we have sin(3x)=cos(2y)
sin(x+pi/3)=cos(y-pi/3)
solve in RxR

Homework Equations

The Attempt at a Solution

i tried squaring both sides and turning everything to cos 2a then turning it into an XY=0
but that didn't help at all i ended up with y=0 which turned out to be wrong

 

[jedishrfu]

you can use the sin & cos of sum of angles:

http://mathworld.wolfram.com/TrigonometricAdditionFormulas.html

to simplify the second equation and go from there