So by the look of it angle D is 90, and because the hypotenuse on both triangles are the same that means that both triangles are the same, so Y would be 2. Also once again a triangles angles add up to 180 and we know that one angle is 51 and the other is 90 then you need to add them together getting 141 and subtract that from 180, getting an answer of 39, if my calculations are correct then X=39 and y=2