The first three rows of the truth table are as follows, where A,B,C,D are inputs and X,Y are outputs:
A B C D X Y
0 0 0 0 1 0
0 0 0 1 1 0
0 0 1 0 0 1
So I'm new to this and not really sure as to how to proceed with finding the boolean expressions for the individual rows. I'd be really grateful if you could provide a brief explanation as to how to do this. Thanks!

 

You might find this helpful:

http://forum.allaboutcircuits.com/blog/boolean-logic-sop-and-pos-forms.583/