Answer:
x = 10, y = 4
Explanation:
since both angles are the same (that is what the angle markings indicate), both triangles are projections from the same point of origin with the same "spread" angle but to different distances.
but in such a case the proportions of all corresponding side lengths in both "projections" or triangles must be the same.
so, 6/9 = "unnamed second part of x"/6
36/9 = 4 = "unnamed second part of x"
and so, x = 6 + 4 = 10.
similarly in the other graphic
3/9 = y/12
36/9 = 4 = y
the straight line "extensions" correspond to each other.
and when you "fold" one triangle over to the other along the same angle you see that in one situation the line of 6 corresponds to the line of 9, and in the other situation the line of y corresponds to the line of 12.
that is why we could do that.